Brown Sugar Butterscotch Cupcakes

Supermoist brown sugar cupcakes filled with homemade butterscotch sauce topped with vanilla frosting and more butterscotch. Indulgent showstopping perfect.
Ingredients
Butterscotch Sauce
14 cup 4 Tbsp 56g unsalted butter
34 cup 150g packed light or dark brown sugar
34 cup 180ml heavy cream
2 teaspoons pure vanilla extract
12 teaspoon salt
Brown Sugar Cupcakes
1 and 23 cup 209g allpurpose flour spooned leveled
12 teaspoon baking powder
14 teaspoon baking soda

12 teaspoon salt
1 cup 200g packed light or dark brown sugar
12 cup 8 Tbsp 113g unsalted butter melted
1 large egg at room temperature
14 cup 60g yogurt
34 cup 180ml milk
1 Tablespoon 15ml pure vanilla extract
Vanilla Frosting
1 cup 16 Tbsp 226g unsalted butter softened to room temperature
34 cups 360480g confectioners sugar
14 cup 60ml heavy cream
2 and 12 teaspoons pure vanilla extract
salt to taste
Instructions
Make the butterscotch sauce In a medium saucepan over medium heat melt the butter. Whisk in the brown sugar then whisk in cream then let mixture bubble and thicken for 5 minutes without stirring. Remove from heat and whisk in vanilla and salt. Allow to cool.
Preheat oven to 350F 177C. Line 12count cupcake pan with liners or spray with nonstick spray. Set aside.
Make the cupcakes Whisk the flour baking powder baking soda and salt together in a medium bowl. Set aside. In a large microwavesafe bowl melt butter in the microwave. Whisk in the brown sugar vigorously until no lumps remain. Whisk in egg yogurt milk and vanilla extract until combined. Slowly mix in dry ingredients until no lumps remain. Batter will be thick. Divide batter between 12 cupcake liners. Bake for 20 minutes or until a toothpick inserted in the center comes out clean. Allow to cool completely before filling.
Make the frosting In a medium bowl beat softened butter on medium speed with an electric or stand mixer fitted with a paddle attachment. Beat for 3 minutes until smooth and creamy. Add confectioners sugar cream