Spinach-Stuffed Turkey Meatloaf

Step 1
Preheat the oven to 375 degrees F (190 degrees C).

Step 2
Lightly grease a medium skillet with cooking spray and place over medium-low heat. Cook and stir mushrooms and onion in the hot skillet until onion is tender, about 4 minutes. Remove from heat.

Step 3
Add spinach, 1/4 cup mozzarella cheese, and Parmesan cheese; mix well and set aside.

Step 4
Combine turkey, oats, milk, egg white, Italian seasoning, salt, and pepper in a large bowl; mix lightly but thoroughly.

Step 5
Spoon 2/3 of the turkey mixture lengthwise down the center of an 11×7-inch glass baking dish. Form a deep indentation down the middle of turkey mixture; fill indentation with spinach mixture.

Step 6
Top with remaining turkey mixture, forming a loaf. Seal the edges to completely enclose spinach filling.

Step 7
Bake in the preheated oven until the juices run clear and an instant-read thermometer inserted into the meat reads 165 degrees F (75 degrees C), 30 to 35 minutes.

Step 8
Sprinkle meatloaf with remaining 1/4 cup mozzarella cheese. Continue baking until cheese melts, 1 to 2 minutes. Let rest for 5 minutes before slicing.