Preheat oven to 350. Spray an 8x8 baking pan with cooking spray and set aside.

Place butter and chocolate chips in a small microwave-safe bowl and microwave on high for 1 minute. Stir until melted. (You can return it to the microwave in 30-second increments as needed.)

In a medium bowl, combine the chocolate mixture with the sugar, applesauce, eggs and vanilla and stir until combined.

Add the flour, baking powder and salt and stir until just combined.

Fold in the diced strawberries, if using. (If you want to add ¼ cup chocolate chips, those go in now too).

Transfer the batter to the prepared baking pan and smooth the top.

Dollop the strawberry jam on top of the batter. I usually do about 9 blobs. Use a toothpick or the tip of a knife to swirl the jam into the batter and get it evenly distributed over the entire pan.

Bake the brownies at 350 for 30-35 minutes, until a toothpick inserted in the center comes out clean.

Let cool slightly in the pan before cutting.

Store the brownies, covered, at room temperature for up to 3 days. After that, they are best stored in the refrigerator.