Peanut Butter Chocolate Chip Cookies

Ok baking experts - explain this to me: I made some cookies the other day and the first few batches out of the oven were flat. But, it seemed that the longer the cookie dough sat, the better the final results were. Admittedly, the batter seemed too soft to begin with. Plus, the baking soda may have been older than desired (does anyone ever finish a box of baking soda - I don't think I ever have). So - why did the batter get better after sitting for about 30-40 minutes? Should I be letting my batter sit regularly?

Here, you can see some of the initial cookies. Flat and dark on the edges. I had to take them out early to avoiding completely burnt edges.

UPDATE: Thanks for your feedback guys! Current theories are either related to the temperature of the butter or the flour. I can't recall what the temperature of the butter was - maybe colder than room temperature? Both suggestions seem likely to be my problem. What about the baking soda? Would old baking soda have an effect?

But, the final product after the batter had sat for a while looks like this:


Peanut Butter Chocolate Chip Cookies
Dorie Greenspan's Baking: From My Home to Yours

2 cups all-purpose flour
1 tsp salt
3/4 tsp baking soda
1 1/2 sticks (12 tablespoons) unsalted butter, at room temperature
1/2 cup peanut butter (chunky or smooth, but not natural)
1 cup sugar
2/3 cup (packed) light brown sugar
2 tsp pure vanilla extract
2 large eggs
12 ouncs bittersweet chocolate, chopped into chips, or 2 cups store-bought chocolate chips or chunks
1 cup finely chopped walnuts or pecans (didn't include nuts)

Center a rack in the oven and preheat the oven to 375 degrees F. Line two baking sheets with parchmentor silicone mats.

Whisk together the flour, salt, and baking soda.

Working with a stand mixer (I used my hand blender), preferably fitted with the paddle attachment, or with a hand mixer in a large bowl, beat the butter and peanut butter at medium speed for about 1 minute, until smooth. Add the sugars and beat for another 2 minutes or so, until well-blended. Beat in the vanilla. Add the eggs one at a time, beating for 1 minute after each egg goes in. Reduce the mixer speed to low and add the dry ingredients in 3 portions, mixing only until each addition is incorporated. On low speed, or by hand with a ruber spatula, mix in the chocolate and nuts. (The dough can be covered andd refrigerated for up to 3 days, or frozen. If you'd like, rounded tablespoonfuls of dough, ready for baking. Freeze the mounds on a lined baking sheet, then bag them when they're solid. There's no need to defrost the ough before baking-just add another minute or two to the baking time.)

Spoon the dough by slightly rounded tablespoonfuls onto the baking sheets, leaving about 2 inches between spoonfuls.

Bake the cookies- one sheet at a time and rotating the sheet at the midway point- for 10-12 minutes, or until they are brown at the edges and golden in the center; they may still be a little soft in the middle, and that's just fine. Pull the sheet from the oven and allow the cookies to rest for 1 minute, then carefully, using a wide metal spatula, transfer them to racks to cool to room temperature.

Repeat with the remainder of the dough, cooling the baking sheets between batches.

Either way - all of the cookies tasted good. But, of course better when the cookie kept its shape in the latter batches.