Pierce potato several times with a fork. On a microwave-safe plate, microwave potato for 3 1/2 minutes.

Flip potato, and microwave for another 3 1/2 minutes, or until soft.

Once cool enough to handle, cut potato in half lengthwise. Use a spoon to gently scoop out the pulp, leaving about 1/4-inch inside the skin. Discard the potato pulp (or reserve for another use).

Bring a skillet sprayed with nonstick spray to medium-high heat. Add chicken, and sprinkle with salt and pepper. Add mushrooms and onion, and cook and stir for about 4 minutes, until chicken is fully cooked and veggies have softened and browned.

Remove skillet from heat. Add marinara sauce, garlic powder, and 1 1/2 teaspoons Parmesan. Stir to coat. Divide mixture between the potato halves.

Sprinkle with remaining 1 1/2 teaspoons Parmesan cheese. 

Makes 1 serving. 

338 calories, 7g fat, 707mg sodium, 31.5g carbs, 4.5g fiber, 5.5g sugars, 37g protein