Whisked by Sonora

May is peak navel orange season in D.C., and I always end up with more oranges than I know what to do with. Citrus desserts have never really been my go-to, not because there’s anything wrong with them, they’ve just never been my personal style. But I am a huge fan of olive oil cake and rum cake, so I started experimenting. After a few rounds of testing, I landed on this upside-down orange rum olive oil cake. It’s bright and vibrant with caramelized orange slices on top, and the flavor hits that perfect balance, rich, warm rum with a light, fresh orange finish. This recipe is basically my love letter to the start of D.C. spring… in cake form.

Difficulty Rating

This recipe is a 3 out of 5 chef hats on the difficulty scale. The trickiest part, in my opinion, is slicing the oranges evenly and removing the seeds without tearing up those “perfect” rounds. Full disclosure: mine were definitely not all even but honestly, the little imperfections give the cake more personality, and it doesn’t affect the flavor at all. If I could give one tip for that step, it’d be to pick a firmer orange. It’s much easier to slice cleanly when the fruit isn’t super soft and overly juicy. Aside from that, the only other moment that can feel a bit fast-paced is pouring the caramel into the pan and getting the oranges arranged before it starts to set. But overall, this is a pretty simple bake.

Song

The song I associate with this recipe is “Golden” by Jill Scott. This cake is bright, funky, vibrant, springy and yes, a little boozy. It has that warm, optimistic feeling, like the part of a movie where everything starts looking up. “Golden” has that same energy, joyful, glowing, and full of forward motion. It’s the kind of song that makes you want to open the windows, let the sun in, and celebrate something, anything, even if it’s just a cake cooling on the counter.

Why These Ingredients Work

Oranges (slices + zest + a little juice)

• Slices become the cake’s “topping” once it’s flipped: they caramelize, turn glossy, and add that slightly marmalade-y bite.
• Zest is where most of the true orange aroma lives and has way more impact than juice. so it makes the cake smell bright and fresh without tasting sour.
• A little juice (optional) reinforces the citrus flavor and keeps the crumb lively.

Brown sugar + butter (the caramel layer)

• Butter gives richness and helps the caramel stay smooth and glossy.
• Brown sugar adds deeper, almost molasses notes that taste incredible with both rum and orange. It also helps the topping stay soft and sticky instead of turning into a hard candy layer.

Olive oil

• Olive oil makes the crumb moist for days (it doesn’t firm up the way butter cakes can).
• It adds a subtle fruitiness that pairs naturally with citrus.
• It also creates a tender, plush texture that works especially well in upside-down cakes.

Eggs

• Eggs provide structure so the cake can support the juicy fruit layer.
• They also emulsify the batter (help the oil and milk blend smoothly), giving you an even, tender crumb.

Milk (or buttermilk)

• Adds moisture and helps dissolve sugar for a softer texture.
• Buttermilk (if you use it) gives a gentle tang that makes the orange taste brighter and balances the sweetness of the caramel.

Sugar in the batter

• Sweetens, of course, but also helps the cake brown and stay tender.
• The sweetness is intentionally moderate because the topping already brings a lot of caramel flavor.

Flour

• Provides the main structure so the cake slices cleanly and doesn’t collapse under the fruit.
• This recipe uses a classic amount so the crumb stays soft, not bready.

Baking powder

• The lift. It gives the cake a light, even rise without needing long beating or extra steps, it’s important because you want a simple batter that bakes reliably under the orange layer.

Salt

• Makes everything taste more like itself: it sharpens the orange, deepens the caramel, and keeps the cake from tasting flat-sweet.

Rum (optional but intentional)

• Rum adds warm, toasty depth that plays beautifully with brown sugar and caramelized oranges.
• Used in a small amount, it doesn’t make the cake “boozy,” it makes it taste more complex and dessert-like, almost like a subtle rum-caramel note.

Vanilla + spices (optional)

• Vanilla rounds out the flavor and makes the orange feel softer and more “baked dessert” than “straight citrus.”
• Cardamom/cinnamon are optional, but they add warmth that bridges the bright orange and the rich caramel.

Finally the Recipe…

Makes: 1 (9-inch) cake
Oven: 350°F (175°C)
Pan: 9-inch round cake pan (parchment on bottom recommended)

Ingredients

Orange topping

• 2 oranges, thinly sliced into rounds (seeds removed)
• 3 tbsp unsalted butter
• 1/2 cup (100g) light brown sugar (or white sugar)
• Pinch of salt
• Optional: 1–2 tsp dark rum (stir in off heat)

Cake

• 1 1/2 cups (190g) all-purpose flour
• 2 tsp baking powder
• 1/2 tsp salt
• 3/4 cup (150g) sugar
• 2 large eggs (room temp)
• 1/2 cup (120ml) olive oil (mild if you prefer)
• 3/4 cup (180ml) milk (or buttermilk)
• Zest of 1–2 oranges
• 2 tbsp orange juice (optional)
• Optional: 1 tsp vanilla OR/AND 1/2 tsp cardamom/cinnamon

Instructions

1. Prep

Preheat the oven to 350°F. Grease your cake pan and line the bottom with parchment paper. The easiest way to size the parchment is to trace the bottom of the pan onto the paper, then cut along the outline. Grease the bottom of the pan, press the parchment round into place, then grease the parchment as well (this helps the cake release cleanly after flipping). I also recommend placing the orange slices in rum and letting them soak overnight to absorb more flavor

2. Caramel Base

In a small saucepan, melt butter + brown sugar + salt. Simmer 1–2 min until glossy. Remove from heat and stir in rum if using. Pour into the pan and tilt to coat the bottom.

3. Arrange Oranges:

Lay orange slices in a single layer over the caramel (overlap a little if needed).

4. Dry Mix

Whisk flour + baking powder + salt (and spice if using).

5. Wet Mix

Whisk sugar + eggs 30–60 sec until smoother. Whisk in olive oil, then milk, zest, and orange juice/vanilla.

6. Combine

Add to wet and whisk just until no flour pockets remain (don’t overmix).

7. Bake

Pour batter gently over oranges. Bake 35–45 min, until a toothpick comes out clean and the top springs back.

8. Flip

Cool 10 minutes (important). Run a knife around the edge, invert onto a plate, lift off the pan, peel parchment.

9. Serve

Serve with a nice cool scoop of vanilla ice cream or on its own. Enjoy and remember to share with the people you love:)

Storage

 Store covered at room temperature for 1–2 days (a cake dome or tightly wrapped works best). For longer storage, refrigerate up to 5 days. Bring slices to room temp before serving for the best texture. You can freeze slices (or the whole cake) by wrapping it tightly in plastic + foil for up to 2 months. Thaw overnight in the fridge or a few hours at room temp.

Notes/Tips

• Olive oil choice: Use a mild extra-virgin olive oil for a subtle flavor, or a more robust one if you want a noticeable olive-oil note.
• Orange bitterness: If your oranges are bitter (some navels can be), blanch the slices in boiling water for 1 minute, then pat dry before arranging.
• Why the 10-minute flip: Invert after about 10 minutes, if you flip it too soon and it can fall apart, and too late and the caramel may stick.
• I recommend soaking the orange slices in rum overnight or for a few Horus to absorb max flavor.
• Slice like a pro: Use a sharp serrated knife and choose firm oranges for cleaner rounds. Remove seeds with the tip of a paring knife or a toothpick.
• Keep it pretty: Overlap slices slightly and keep them in a single layer so the cake flips cleanly.
• Don’t overmix: Stir just until the flour disappears, overmixing makes the crumb tougher.
• Check doneness smartly: If the top browns early, tent loosely with foil for the last 10 minutes. The cake is done when a toothpick comes out clean.
• Easy release insurance: Parchment on the bottom + greasing the parchment makes a huge difference.
• Optional rum add: Add 1–2 tsp rum to the caramel off heat, or 1 tbsp to the batter (reduce milk by 1 tbsp).