Preheat the oven to 350°F (175°C). Line 2 large baking sheets with parchment paper and set aside.
In a large bowl, beat together the 1/2 cup softened unsalted butter and 1/2 cup spreadable peanut butter until creamy.
Add the 2/3 cup packed light brown sugar, 1/2 cup white granulated sugar, and 2 teaspoons pure vanilla extract; beat until smooth.
Beat in the 1 large egg until fully incorporated.
Add the 1 1/2 cups all-purpose flour, 1/2 teaspoon baking powder, and 1/3 teaspoon salt. Fold the dry ingredients into the wet ingredients until just combined and a soft dough forms—do not overmix.
Stir in half of the 3/4 cup semi-sweet (or dark) chocolate chips with your fingers or a wooden spoon.
Roll the dough into about 15 balls and place them on the lined baking sheets, leaving space between each cookie for spreading.
Press the remaining chocolate chips onto the top of each cookie.
Bake for about 10–11 minutes, until the tops are lightly golden. Do not overbake.
Remove the baking sheets from the oven, let the cookies rest on the sheet for a few minutes, then transfer them to a wire rack and allow to cool for about 15 minutes.