01 -
Set your oven to 350°F. Grab a 9x13 pan and line it with parchment, leaving the edges to hang over for easy removal. No parchment? Spray it really well with non-stick spray.
02 -
Use an electric hand mixer or a stand mixer with a paddle. In a big mixing bowl, blend the melted butter, peanut butter, eggs, vanilla, white sugar, and brown sugar until it's creamy and smooth.
03 -
Toss in the flour, salt, and baking soda. Use low speed to stir until you can't see any dry flour bits. Stop mixing as soon as it's combined—don't overdo it!
04 -
Fold in most of the Reese's chunks and chocolate chips. Save a little of each to sprinkle on top later. Mix just enough so they're spread out evenly.
05 -
Push the dough into your pan so it spreads evenly. Use your hands or a spatula to smooth the surface. Top with the left-over Reese's and chocolate chips, pressing them lightly into the dough.
06 -
Bake for 25 to 30 minutes. When the edges are golden and a toothpick poked in the middle comes out mostly clean (some gooey crumbs are fine), take it out. Let it cool fully before cutting it up.