Bars and photo by sugarpie © Sarah Phillips

These are not for the faint-hearted because the recipe delivers an incredible mix of flavors and textures – chewy and rich peanut butter bars laced with gooey bittersweet chocolate. You'll need plenty of napkins when you eat them! The dough is stiff, so it needs to be pressed into a greased baking pan. After baking and cooling, cut them into bars in advance, if desired, and place in an airtight container, or just cover the entire pan with plastic wrap or foil. They freeze nicely.
COOKIE RECIPE HELP

INGREDIENTS
2 1/3 cups unbleached all-purpose flour; spoon into measuring cup and level to rim
2 1/2 teaspoons baking powder
3/4 teaspoon salt

1/2 cup (1 stick) unsalted butter, melted
1 1/4 cups sugar
1 cup dark brown sugar, packed

1 cup chunky peanut butter; measure with a dry measuring cup and level to rim

3 large eggs, room temperature
2 teaspoons vanilla extract

2 cups (one 11.5 or 12-ounce bag) semisweet chocolate chips; you can substitute with bittersweet or white chocolate chips
SARAH SAYS: I use Ghirardelli 60% Cacao Bittersweet Chocolate Chips (formerly Double Chocolate). If you cant find them, chop a bittersweet baking chocolate bar, found in the grocery store, into 1/4-inch evenly sized pieces. Measure 1 1/2 cups for the recipe when using baking chocolate.

NOTES: Do not use a hand held mixer with this recipe; the dough is really thick and may burn out its motor.

INSTRUCTIONS
1. Position a rack in the center of the oven and preheat it to 350 degrees F. Line a 9 x 13-inch baking pan with parchment paper or spray the pan with nonstick spray.
SARAH SAYS: Don't forget to lower the oven temperature by 25 degrees F if you use a dark nonstick, heavy ceramic or ovenproof glass pan.

2. In a medium bowl, combine the flour, baking powder, and salt. Set aside.

3. Fit a stand mixer with a paddle attachment, and in the bowl of a stand mixer, add the sugars and with the mixer on low, drizzle in the melted butter. Add the peanut butter and mix until incorporated.

4. Add the eggs and vanilla and incorporate with the mixer on low. Take care not to beat air into the dough; just mix until the ingredients are incorporated. The dough will be really sticky and thick. Stop the mixer and scrape the bottom and side of the bowl often.

5. With the mixer on low, add the flour mixture in a fast stream at the side of the bowl until incorporated. Do not overmix. The dough will be really stiff. At the end, add in the chocolate chips. The chips will not incorporate well, but it's ok.

6. PRESS the dough evenly in the baking pan. Gather any stray chocolate chips at the bottom of the mixing bowl and sprinkle on top of the dough and then lightly press in. The dough will fill the pan about 1/4 to 1/2-inch thick.

7. Bake for about 30 minutes until lightly browned around the edges and lightly browned on top. The recipe will seem underdone in the middle but will harden when cool. Do not overbake. The bars will be about 1-inch thick.

Cool in the pan on a wire cake rack before cutting into bars. The recipe will take about 2 hours to cool thoroughly.
SARAH SAYS: The bars are delicious when eaten slightly warm!

STORAGE
Store well-covered at room temperature for 3 to 5 days. Freezes well for up to 3 months in an airtight container.