Step 1

Preheat oven to 375 degrees. Line a 12-cup muffin pan with foil baking cups, or spray with nonstick spray.

Step 2

In a large bowl, combine both types of flour, powdered peanut butter, protein powder, sweetener, baking soda, baking powder, and salt. Mix well.

Step 3

In a medium-large bowl, combine applesauce, yogurt, egg whites/substitute, and vanilla extract. Add 1 cup water, and whisk until uniform. Add mixture to the large bowl, and stir until uniform. (Batter will be thick.)

Step 4

Fold strawberries into the batter. Evenly distribute batter among the cups of the muffin pan, and smooth out the surfaces. (Cups will be full.)

Step 5

Bake until a toothpick inserted into the center of a muffin comes out clean, 20 - 22 minutes.

Step 6

Let cool completely, about 10 minutes in the pan and 15 minutes out of the pan.

Step 7

Use a knife or narrow spoon handle to create a centered indentation through the top of each muffin about 1/2-inch wide, stopping about 3/4ths of the way through.

Step 8

Add preserves to one of the bottom corners of a sealable plastic bag. Remove air and seal. Snip off a small part of that corner with scissors.

Step 9

Gently squeeze the bag, and evenly pipe mixture through the hole in the bag's corner and into the holes in the muffins.