Gather your ingredients and spray the inside of a 6-quart crock pot with non-stick cooking spray.
Whisk together the milk, melted butter, and vanilla in a large bowl.
Add the flour, sugar, cocoa powder, baking powder, and salt and mix until just combined. Pour the batter into the bottom of the crock pot.
To Make the Topping
In a medium bowl, mix the sugar, brown sugar, and cocoa powder until combined. Sprinkle evenly over the cake batter in the crockpot.
Pour the hot water over the cake batter and topping. DO NOT STIR. Cover and cook on HIGH 2.5 to 3 hours or LOW for 4 hours. The cake is done when the top is dry, and a toothpick inserted in the middle comes out clean.
To Serve
Serve warm with ice cream or whipped cream, and don’t forget to spoon some of the chocolate sauce from the bottom of the slow cooker over the top.
Notes
Don't forget to spray your crock with non-stick cooking spray before adding your ingredients. All slow cookers cook differently, so suggested cooking times are a basic guideline. Recipes should always be tested first in your slow cooker, and cooking time should be adjusted as needed.To Store: Transfer leftover Slow Cooker Lava Cake to an airtight container and store in the refrigerator for 3-4 days. To reheat, warm in the microwave in 30-second intervals. The serving size is approximately a 2-inch piece of cake.Nutritional information is approximate and was calculated using a recipe nutrition label generator and will vary based on cooking methods and brands of ingredients used. It does not include the toppings.