Sort ingredients
arblum2
QR Code
Listen
PdfHeat oven to 350°F.
Mix dough exactly as directed for cookies (mix + softened butter + egg).
Fold in M&Ms (save a small handful to sprinkle on top if you want it pretty).
Press dough evenly into a greased or parchment-lined 9×13 pan.
For thicker bars, use a 9×9 and expect a slightly longer bake.
Bake: 9×13: 18–22 minutes; 9×9: 22–28 minutes.
Pull them when the edges are set and lightly golden, but the center still looks a little soft.
Cool completely before cutting (this matters for clean bars).