10 Tbl. unsalted butter, browned
1 c. brown sugar, packed
1/4 c. white sugar
1 egg
2 tsp. vanilla extract
1 1/4 c. all-purpose flour
1 1/4 tsp. baking powder
1/4 tsp. kosher salt
1 1/4 c. M&M's
Preheat oven to 350 degrees. Line an 8x8-inch baking dish with parchment paper and spray with cooking spray. Melt butter in a small saucepan over medium heat. Allow it to boil, stirring occasionally, until browned. It will begin to smell nutty and it will get foamy when it is ready. It goes from yellow to brown very quickly, so watch closely. Allow to cool for 5 minutes or so. In a medium bowl, mix together the browned butter, brown sugar and white sugar. Add the egg and vanilla and mix well. Add the flour, baking powder and salt and mix until combined. Stir in 1 cup of M&M's. Press evenly into prepared baking pan and sprinkle the remaining 1/4 cup of M&M's over the top. Bake for 30 minutes. Cool completely before serving.
Jenn's Notes: The original recipe suggested baking for 25 minutes, but mine were so jiggly and underdone, that I baked them 5 minutes longer. I cut into them while they were still warm and they were still runny and gooey and I thought they were underdone, but once they cooled completely, they were great.
adapted from: Recipe Girl