Quick Recipe Version (TL;DR)
Quick Ingredients
- 4 medium tart apples (about 2 lb/900 g), 1 tbsp lemon juice
- Caramel: 3/4 cup (150 g) granulated sugar, 2 tbsp water, 3 tbsp (42 g) unsalted butter, 1/4 tsp fine sea salt
- Batter: 1/2 cup (113 g) unsalted butter, 3/4 cup (150 g) granulated sugar, 2 large eggs, 1 1/2 tsp vanilla
- 1/2 cup (120 ml) buttermilk
- 1 1/2 cups (180 g) all-purpose flour
- 1 1/2 tsp baking powder, 1/4 tsp baking soda, 1/2 tsp fine sea salt
- Optional: 1/2 tsp cinnamon, pinch nutmeg, flaky sea salt, whipped cream or vanilla ice cream
Do This
- 1) Heat oven to 350°F (175°C). Brown 1/2 cup butter until nutty and amber; cool until warm.
- 2) Make caramel: Cook 3/4 cup sugar + 2 tbsp water to deep amber; off heat whisk in 3 tbsp butter + 1/4 tsp salt. Immediately pour into a 10-inch cast-iron skillet.
- 3) Peel, core, and slice apples 1/4-inch thick; toss with lemon juice (and cinnamon/nutmeg if using). Fan apples over caramel.
- 4) Batter: Whisk 3/4 cup sugar + 2 eggs until pale; whisk in vanilla and the cooled brown butter. Fold in dry ingredients, alternating with buttermilk.
- 5) Spread batter over apples. Bake 35–40 minutes until golden and a tester comes out with a few moist crumbs.
- 6) Cool 10 minutes, loosen edges, invert onto a large plate. Spoon any caramel from skillet over top; finish with flaky salt.
Why You’ll Love This Recipe
- Dark, bittersweet caramel meets tart apples for a perfectly balanced bite.
- One skillet bake: caramel, apples, and batter come together with minimal dishes.
- Brown-butter batter adds nutty depth and a tender, moist crumb.
- Flip for a dramatic reveal of glossy, fanned fruit that looks bakery-worthy.
Grocery List
- Produce: 4 tart apples (Granny Smith, Honeycrisp, or Pink Lady), 1 lemon
- Dairy: Unsalted butter (1 1/2 sticks total), 2 large eggs, buttermilk
- Pantry: Granulated sugar, all-purpose flour, baking powder, baking soda, vanilla extract, fine sea salt, ground cinnamon and nutmeg (optional), flaky sea salt (optional)
Full Ingredients
For the Caramel
- 3/4 cup (150 g) granulated sugar
- 2 tbsp (30 ml) water
- 3 tbsp (42 g) unsalted butter, cut into cubes
- 1/4 tsp fine sea salt
- Optional but helpful: 1 tbsp light corn syrup (to prevent crystallization)
For the Apple Layer
- 4 medium tart apples (about 2 lb/900 g), such as Granny Smith, Honeycrisp, or Pink Lady
- 1 tbsp lemon juice
- Optional: 1/2 tsp ground cinnamon, pinch nutmeg
For the Brown-Butter Cake Batter
- 1/2 cup (113 g) unsalted butter
- 3/4 cup (150 g) granulated sugar
- 2 large eggs, at room temperature
- 1 1/2 tsp pure vanilla extract
- 1/2 cup (120 ml) buttermilk, at room temperature
- 1 1/2 cups (180 g) all-purpose flour
- 1 1/2 tsp baking powder
- 1/4 tsp baking soda
- 1/2 tsp fine sea salt
To Finish (Optional)
- Flaky sea salt, for sprinkling
- Lightly sweetened whipped cream or vanilla ice cream, for serving
Step-by-Step Instructions
Step 1: Preheat and set up
Preheat the oven to 350°F (175°C) with a rack in the center. Place a 10-inch cast-iron skillet on a sturdy sheet pan (to catch any caramel drips). Have a large, heatproof serving plate ready for inverting later.
Step 2: Brown the butter for the batter
Add 1/2 cup (113 g) unsalted butter to a light-colored saucepan over medium heat. Melt, then continue cooking, swirling often, until the milk solids turn deep golden and smell nutty, 5–7 minutes. Immediately scrape the brown butter and all toasted bits into a heatproof bowl. Cool until warm, not hot, about 5–10 minutes.
Step 3: Make a dark caramel and pour into the skillet
In a small heavy saucepan, combine 3/4 cup (150 g) sugar and 2 tbsp water (plus the optional 1 tbsp corn syrup). Cook over medium-high heat without stirring until the syrup turns a deep amber, 5–8 minutes. If needed, gently swirl the pan to even out color. Off the heat, carefully whisk in 3 tbsp (42 g) butter and 1/4 tsp salt; it will bubble vigorously. Immediately pour the hot caramel into the 10-inch cast-iron skillet, tilting to fully coat the bottom in an even layer.
Safety note: Caramel is extremely hot. Keep kids and pets away, and avoid touching the caramel or pan.
Step 4: Fan the apples over the caramel
Peel, core, and slice apples into 1/4-inch-thick wedges. Toss with 1 tbsp lemon juice (and the cinnamon and nutmeg if using). Working quickly, arrange the slices in tight concentric circles over the caramel, overlapping each piece to create a fanned pattern. Tuck extra slices into gaps—you want a snug, even layer.
Step 5: Mix the brown-butter batter
In a large bowl, whisk 3/4 cup (150 g) sugar and the 2 eggs until pale and slightly thick, about 60 seconds. Whisk in the vanilla. While whisking, slowly drizzle in the cooled brown butter until fully incorporated.
In a separate bowl, whisk together the flour, baking powder, baking soda, and salt. Add the dry mixture to the egg mixture in two additions, alternating with the buttermilk, beginning and ending with the dry. Stir gently just until no dry spots remain; do not overmix.
Step 6: Bake until golden and set
Scrape the batter over the apples and smooth the top. Bake until the cake is golden, the center springs back, and a toothpick inserted near the center comes out with a few moist crumbs, 35–40 minutes. If the top is browning too quickly, tent loosely with foil for the last 5 minutes.
Step 7: Flip to reveal the glossy fruit
Transfer the skillet to a rack and cool for 10 minutes. Run a thin knife around the edges to loosen. Place your serving plate over the skillet, grip with oven mitts, and invert in one confident motion. Let it sit for 30 seconds, then lift off the skillet. If any apples or caramel stick to the pan, simply spoon them back on. Sprinkle with a pinch of flaky sea salt and serve warm with whipped cream or vanilla ice cream.
Pro Tips
- Caramel color guide: Aim for deep amber (like dark honey). Too pale tastes sweet; too dark tastes bitter.
- Cool brown butter until warm before adding to eggs to prevent curdling.
- Pack the apples tightly—they shrink as they bake, and a snug layer gives a clean, glossy top.
- Invert while warm: 10 minutes is the sweet spot. Any longer and the caramel may set too firmly.
- For precision, the cake is done when the center registers about 200°F (93°C) on an instant-read thermometer.
Variations
- Salted Rum Caramel: Off heat, whisk 1 tbsp dark rum or apple brandy into the caramel with the butter, and finish the cake with an extra pinch of flaky salt.
- Almond Twist: Replace 1/4 cup (30 g) of the flour with finely ground almond flour and add 1/4 tsp almond extract to the batter.
- Pear & Ginger: Swap apples for firm pears and add 1/2 tsp ground ginger to the batter.
Storage & Make-Ahead
Store leftovers covered at room temperature for up to 1 day or refrigerated for up to 4 days. Rewarm slices in a 300°F (150°C) oven for 8–10 minutes or microwave briefly to loosen the caramel.
Make-ahead: Brown the butter up to 1 week in advance and refrigerate; gently rewarm to liquid before using. You can also make the caramel and pour it into the skillet up to 4 hours ahead; it will firm as it cools and re-liquefy in the oven. The baked cake freezes well—wrap slices tightly and freeze up to 2 months; thaw and warm before serving.
Nutrition (per serving)
Approximate: 435 calories; 21 g fat; 67 g carbohydrates; 5 g protein; 2 g fiber; 350 mg sodium.
