Why do my cookies look like this?

I could have sworn I followed the recipe precisely. I let the brown butter cool. Could my baking powder be old? They should bake flat Here is the recipe with reference pictures: https://bromabakery.com/best-chocolate-chip-cookies/

I could have sworn I followed the recipe precisely. I let the brown butter cool. Could my baking powder be old? They should bake flat Here is the recipe with reference pictures: https://bromabakery.com/best-chocolate-chip-cookies/