Preheat oven to 350 degrees Fahrenheit and line a standard muffin tin with 10 cupcake liners. Fill the remaining two cups almost halfway with water.
Whisk together flour, baking soda, cinnamon, and salt. Set aside.
In a separate bowl, beat vegetable oil, granulated sugar, and brown sugar well. Add egg and vanilla then beat until evenly combined.
Gradually mix the dry mixture into the wet mixture.
Stir in apples.
Divide batter evenly between baking cups, filling each about 2/3 full.
Bake for 20-25 minutes, until a toothpick inserted in the center comes out clean and the edges are barely golden.
Prepare the topping while the cakes are baking. Heat butter, milk, and brown sugar in a small saucepan over medium heat. Bring to a boil, turn the heat to medium low, and let simmer for about 3 minutes, stirring occasionally. Transfer to a small bowl or cup.
Remove cakes from oven. Poke a hole, about a centimeter in diameter, in the center of each one. A chopstick or the back of a utensil works well for this. Spoon a generous amount of topping on each cake, spreading it over the top and allowing it to seep into the middle.
Savor them warm OR refrigerate and enjoy them chilled!
10 servings
1 cake