For the Edible Cookie Dough:

1. Heat-treat the flour by spreading it on a baking sheet and baking at 350°F (175°C) for 5-7 minutes. Cool before use.

2. In a bowl, cream together butter, brown sugar, and granulated sugar until light and fluffy.

3. Mix in vanilla extract and milk.

4. Gradually add the heat-treated flour and mix until combined.

5. Fold in mini chocolate chips. Set aside.

For the Cupcakes:

1. Preheat oven to 350°F (175°C). Line a 12-cup muffin tin with cupcake liners.

2. In a medium bowl, whisk together flour, baking powder, salt, and chocolate chips.

3. In a large bowl, combine melted butter and sugar. Beat in eggs, egg white, milk, and vanilla extract until smooth.

4. Gradually add dry ingredients to wet ingredients, mixing until just combined.

5. Fill cupcake liners about ⅔ full. Bake for 18-20 minutes, or until a toothpick inserted comes out clean. Cool completely on a wire rack.

For the Brown Sugar Buttercream:

1. In a saucepan, melt brown sugar with 2 tablespoons water over medium heat until it boils. Boil for 1 minute, then immediately transfer to a bowl. Let cool completely.

2. In a large bowl, beat softened butter until creamy.

3. Gradually add confectioners sugar and cooled brown sugar syrup, alternating with heavy cream.

4. Beat in vanilla extract and salt. Whip until fluffy.

Assembly:

1. Once cupcakes are cooled, optionally hollow out a small center and fill with edible cookie dough.

2. Pipe or spread brown sugar buttercream on top of cupcakes.

3. Garnish with a small spoonful of cookie dough or mini chocolate chips if desired.