Preheat oven to 400 degrees F (200 degrees C). Line 6 muffin cups with paper liners; spray the inside of each paper liner with cooking spray.
Mix flour, sugar substitute, baking powder, and salt together in a bowl. Whisk almond milk, egg substitute, applesauce, butter, and vanilla extract together in a separate bowl; stir almond milk mixture into flour mixture. Fold in strawberries. Spoon batter into the prepared muffin cups.
Bake in the preheated oven until a toothpick inserted in the center of a muffin comes out clean, 20 to 22 minutes.
1 cup whole wheat flour
2 tablespoons stevia sugar substitute (such as Truvia®)
1 1/2 teaspoons baking powder
1/4 teaspoon salt
1/2 cup almond milk
1/4 cup egg substitute (such as Egg Beaters®)
3 tablespoons unsweetened applesauce
1 tablespoon unsalted butter, melted
1/2 teaspoon pure vanilla extract
1 cup sliced fresh strawberries