Keto Pineapple Upside-Down Cake – Moist, Buttery, and Just 3.8g Net Carbs

I didn’t think I’d ever make a pineapple upside-down cake on keto that didn’t taste like a compromise. But here we are. This version uses real pineapple (yes, in moderation), a buttery erythritol caramel layer, and a soft almond flour cake that holds together like the original—but with none of the bloat or blood sugar rollercoaster.

💡 Why This One Works So Well (Low-Carb Edition)

Let’s be real: pineapple’s not a low-carb fruit. But this cake uses just 3 small rings across 12 slices, giving you that sweet-tart flavor without blowing your macros.

Here’s what makes it work:

• Brown erythritol + butter = faux caramel topping
• Thinly sliced pineapple = max flavor, minimal carbs
• Almond flour batter = moist, not gritty, with solid structure
• Pineapple extract = boosts tropical flavor without sugar

🧾 Smart Swaps and Why They Matter

🍍 For the Topping

• 3 tbsp softened butter – Greases and caramelizes the pan base.
• 3 tbsp brown erythritol – Gives that brown sugar glaze vibe.
• 3 fresh pineapple rings (100g) – Sliced super thin to control carbs.
• 3–6 raspberries – Optional but cute in the center of each ring.

🍰 For the Cake

• 3 large eggs – Room temp = fluffier texture.
• ½ cup granulated sweetener – Erythritol or allulose.
• ⅓ cup unsweetened almond milk – Lightens the batter.
• 2 tsp baking powder + ¼ tsp sea salt – Structure and flavor.
• 1 tsp vanilla + 2 tsp pineapple extract – Tropical depth.
• ½ cup melted butter – Richness and fat to bind the almond flour.
• 3 cups almond flour – Use fine almond flour for the best texture.

🔁 Low-Carb Substitutions That Hold Up

Swap	What It Changes	My Take
Pineapple → grilled zucchini coins + pineapple extract	Fewer carbs, still tropical	If you’re very strict keto
Butter → coconut oil	Dairy-free, still rich	Works great, adds a light coconut note
Brown erythritol → allulose blend	Softer “caramel” effect	Allulose browns beautifully

⚠️ Keto Missteps and How I Fixed Them

What Went Wrong	Why It Happens	How to Fix It
Cake was soggy on bottom	Pineapple not patted dry	Use paper towels before baking
Top over-browned	No foil tent after 25 mins	Cover loosely with foil partway
Crumb fell apart	Overmixed or too little fat	Stir until just combined, don’t skimp on butter
Eggy taste	Butter too hot cooked eggs	Cool melted butter before mixing in

👩‍🍳 How to Make It (Step-by-Step)

1. Preheat oven to 350°F (180°C). Grease a 9″ springform pan with butter and line bottom with brown erythritol-butter paste.
2. Arrange pineapple rings on the bottom, placing a raspberry in the center of each.
3. In a large bowl, whisk eggs, sweetener, almond milk, baking powder, salt, vanilla, and pineapple extract.
4. Stir in melted (not hot) butter.
5. Gradually fold in almond flour until a thick batter forms.
6. Pour batter gently over fruit layer.
7. Bake 40–45 minutes, tent with foil after 25 to prevent overbrowning.
8. Cool in pan for 30 mins, then invert and cool fully on a rack (3 hours minimum).
9. Optional: brush with sugar-free pineapple syrup for gloss.

🧠 My Go-To Low-Carb Hacks

• Use a microplane to add a little fresh lemon zest to the batter—adds brightness.
• Chill overnight before slicing = tighter crumb + cleaner slices.
• Want extra caramel? Sprinkle extra brown erythritol over pineapples before batter.

🧊 Freezing + Reheating Without Ruining It

• Fridge: Store covered up to 4 days.
• Freezer: Slice and wrap individually. Thaw at room temp or rewarm gently.
• Best served slightly chilled or room temp—warm will soften the fruit too much.

❓ Real Keto Questions, Real Answers

Is pineapple keto?
Not typically. But 3 rings spread over 12 slices keeps it under 3.8g net carbs per serving. That’s reasonable for most low-carb eaters.

Can I use canned pineapple?
Yes—but only no sugar added varieties. Drain and pat dry very well.

Can I make this dairy-free?
Yes—use coconut oil and non-dairy milk like almond or macadamia.

Will it still caramelize without sugar?
Yes, if using brown erythritol or allulose, which mimic sugar’s caramel behavior.

📊 Full Nutrition Facts – Per 1 Slice (Out of 12)

Nutrient	Amount
Calories	271.7 kcal
Total Fat	25.6 g
– Saturated Fat	6.8 g
Cholesterol	66.8 mg
Sodium	246.5 mg
Total Carbs	6.8 g
– Fiber**	3 g
– Net Carbs	3.8 g
Protein	7.7 g
Sugar	1.1 g
Calcium	117 mg
Iron	1.4 mg
Vitamin A	429 IU

Check out More Recipes:

• Sugar-Free Cupcakes – Moist, Fluffy, and Frosted to Perfection
• Keto Lemon Cake – Sugar-Free, Fluffy, and Full of Zing
• Keto Chocolate Cake – Sugar-Free, Moist, and Actually Fluffy