Let’s bake these comforting “Lunch Lady” Peanut Butter Cookie Bars:

1. Preheat Oven and Prepare Pan:

• Preheat your oven to 350°F (175°C).
• Line an 8×8-inch baking pan with parchment paper, leaving a slight overhang on two opposite sides to act as “handles.” Alternatively, lightly grease the pan thoroughly.

2. Make the Cookie Dough (Creaming):

• In a large mixing bowl (or the bowl of a stand mixer), add the softened unsalted butter, granulated sugar, and packed brown sugar.
• Using a hand mixer or a stand mixer with the paddle attachment, cream these ingredients together on medium-high speed until the mixture is light in color and fluffy in texture. This should take about 3-4 minutes. Scrape down the sides of the bowl as needed.

3. Add Wet Ingredients:

• Add the creamy peanut butter to the creamed butter and sugar mixture. Continue mixing until it’s smooth and well incorporated.
• Next, beat in the large eggs, one at a time, mixing well after each egg is added until it’s fully incorporated.
• Stir in the vanilla extract.

4. Combine Dry Ingredients and Finish Dough:

• In a separate medium bowl, whisk together the all-purpose flour, baking powder, and salt.
• Gradually add the dry ingredients to the wet ingredients in the large bowl. Mix on low speed just until the dough comes together and no large streaks of flour remain. Be careful not to overmix!

5. Press Dough into Pan:

• Transfer the prepared cookie dough to your prepared 8×8-inch baking pan.
• Use a spatula or your lightly floured hands to spread and press the dough evenly into the pan, creating a smooth, flat layer.

6. Bake the Bars:

• Place the pan in the preheated oven.
• Bake for 20-25 minutes. The bars are done when the edges are golden brown and the center is set (it shouldn’t look wet or jiggly). A toothpick inserted into the center should come out clean or with a few moist crumbs attached.

7. Cool Completely (Crucial Step!):

• Remove the pan from the oven and place it on a wire rack.
• Let the bars cool completely in the pan before attempting to glaze them. This can take 1-2 hours or longer. Glazing warm bars will result in a runny, melted mess.

8. Make and Apply the Glaze:

• Once the bars have cooled completely, prepare the glaze. In a small bowl, whisk together the sifted powdered sugar, 2 tablespoons of milk (or cream), and ½ teaspoon vanilla extract until smooth. If the glaze is too thick, add more milk, a tiny bit at a time. If too thin, add more sifted powdered sugar.
• Drizzle or spread the glaze evenly over the top of the cooled peanut butter bars.

9. Add Optional Toppings:

• If you’re using them, immediately sprinkle your choice of toppings (sprinkles, chopped peanuts, or mini chocolate chips) over the wet glaze before it sets.
• Let the glaze set for about 20-30 minutes before slicing and serving.

Patience during cooling is key for perfect glazing and slicing