This 4-Ingredient Slow Cooker Burnt Sugar Custard Cake combines caramelized sugar with a milk-and-egg batter for a soft, spoonable dessert. Self-rising flour gives the filling some body, while the caramel forms a sweet amber layer beneath it.
What You’ll Need
- Granulated sugar. Use 1 cup total, reserving ¾ cup for the caramel and ¼ cup for the batter.
- Whole milk. Three cups provide the liquid for the custard-style filling.
- Eggs. Four large eggs help the filling set during cooking.
- Self-rising flour. One cup adds structure and contains its own leavening and salt.
Choose a Pan That Fits
Use a solid, food-safe metal baking pan with at least a 2-quart capacity that fits inside your slow cooker with the lid fully closed. Leave space around the pan for water. Check the fit before starting, and follow your appliance manufacturer’s instructions for cooking with an inner dish.
Set the pan on a small heatproof rack inside the insert. Water added around the pan creates a gentle cooking environment. Water and a little grease for the pan are additional to the four main ingredients.
How to Make the Caramel
Place ¾ cup sugar in a dry, heavy saucepan over medium heat. Let it begin melting, then gently swirl the pan to distribute the liquid sugar. Cook until deep amber, watching closely as the color develops.
Carefully pour the caramel into the lightly greased metal baking pan. Using oven mitts, gently tilt the pan to coat the bottom. Set it on a heatproof surface and let the caramel harden and the pan cool before adding the batter.
Mix the Custard Cake Batter
Gently warm the milk in a saucepan, then let it cool until lukewarm. Whisk the eggs and remaining ¼ cup sugar together in a large bowl. Whisk in the self-rising flour just until incorporated.
Gradually whisk in the lukewarm milk to make a thin batter. Pour it over the hardened caramel in the cooled metal pan.
How to Cook the Custard Cake
Cover the baking pan with foil and set it on the rack inside the room-temperature slow cooker insert. Carefully add lukewarm water around the pan to reach approximately halfway up its sides, keeping the water below the rim.
Close the slow cooker lid and cook on LOW. Begin checking around 3 hours. Allow approximately 3–4 hours or longer, depending on the appliance and pan depth.
The edges should be set and the center should have a gentle wobble without liquid batter. Check that the center reaches at least 160°F. Temperature and texture should guide the cooking time.
Rest and Serve
Turn off the slow cooker. Carefully remove the lid and foil, keeping escaping steam away from your hands and face. Let the dessert rest for 20–30 minutes before serving.
Scoop directly from the inner pan into bowls, including caramel from the bottom. Expect a soft pudding-style dessert. The amount of free-flowing caramel sauce and the firmness of the filling may vary.
Frequently Asked Questions
Does burnt sugar mean blackened caramel?
Aim for deep amber caramel with a toasted aroma. Blackened sugar will give the dessert a harsh, bitter flavor.
Can I use plain all-purpose flour?
Self-rising flour contains added leavening and salt. Plain flour requires adjustments to recreate that mixture.
Why is my custard cake still loose?
The cooking time depends on the depth of the batter and your slow cooker. Continue cooking until the center reaches the stated temperature and has set without liquid batter.
Will it slice like a regular cake?
This recipe is intended as a soft, spoonable dessert. Serve it in bowls with the caramel underneath.
4-Ingredient Slow Cooker Burnt Sugar Custard Cake Recipe Card
A soft custard-style cake cooked over amber caramel in a metal pan inside the slow cooker.
- Prep time — About 25 minutes, plus cooling
- Cook time — Approximately 3–4 hours or longer on LOW
- Rest time — 20–30 minutes
- Servings — 6–8
Ingredients
- 1 cup granulated sugar, divided
- 3 cups whole milk
- 4 large eggs
- 1 cup self-rising flour
Equipment and Preparation
- A slow cooker large enough to hold the inner pan with its lid closed
- A solid metal baking pan with at least a 2-quart capacity
- A small heatproof rack and aluminum foil
- A little butter or cooking spray for greasing
- Lukewarm water for the water bath
Instructions
- Check that the metal pan fits inside the slow cooker on a rack, with space around it and the lid fully closed. Lightly grease the pan.
- Heat ¾ cup sugar in a heavy saucepan over medium heat. Once melting begins, gently swirl until the sugar is melted and deep amber.
- Carefully pour the caramel into the metal pan. Using oven mitts, tilt gently to coat the bottom. Let the caramel harden and the pan cool on a heatproof surface.
- Warm the milk gently, then let it cool until lukewarm.
- Whisk the eggs with the remaining ¼ cup sugar. Whisk in the self-rising flour just until incorporated, then gradually whisk in the lukewarm milk.
- Pour the batter over the hardened caramel. Cover the pan with foil.
- Place the rack and filled pan inside the room-temperature slow cooker insert. Add lukewarm water around the pan to approximately halfway up its sides, below the rim.
- Close the slow cooker lid and cook on LOW. Begin checking around 3 hours. Continue until the center reaches at least 160°F (71°C), the edges are set, and the center gently wobbles without liquid batter. Cooking may take 3–4 hours or longer.
- Turn off the cooker. Carefully remove the lid and foil, avoiding steam, and rest for 20–30 minutes.
- Scoop into bowls, including the caramel from the bottom, and serve warm.
Recipe Notes
- This adapted method has not been kitchen-tested. Cooking time and final texture may vary.
- Use a thermometer and check the texture to determine doneness.
- Pour the hot caramel into the metal pan and let it cool before assembly.
- Expect a soft, spoonable texture.
- Water-bath water and pan grease are additional to the four main ingredients.