My daughter and I made these cookies for Easter and they might be the best cookies I've ever baked.
Preheat oven to 325 degrees F.
Mix together and set aside:
2 C plus + 2 Tbsp All purpose flour
1/2 tsp baking soda
In another bowl, mix together:
1 and 1/2 sticks of non-salted butter, melted and cooled
1 C dark brown sugar, lightly packed
1/2 granulated sugar
Stir into butter/sugar mix:
1 whole egg and 1 egg yolk, at room temperature
1/2 tsp salt
2 tsp vanilla extract
Gradually add flour mix until dough forms. Fold in M&Ms.
Roll dough into 2 Tbsp portions and place on ungreased air insulated stainless steel cookie sheet about 2 inches apart. If you want, you can add more M&Ms to the tops of each cookie before baking to make sure each cookie has a colorfully decorated surface. Bake for 8 -12 minutes. Oven temperatures vary, but I found my cookies did best at just about 11 minutes. Don't over bake unless you want very crunchy cookies. Let cool for at least 5 minutes.