Combine broth and pearl barley and bring to a boil. 

Reduce heat to low and simmer 45 minutes or until tender but not until they lose their shape. Drain any excess liquid. 

While the barley is cooking, heat the olive oil in a large skillet. Cook garlic and onion until onions are translucent, then add chicken. Brown and drain. Refrigerate chicken until needed. 

Cut each pepper in half vertically. Remove all seeds and white membrane, but leave the stem in place. 

When barley is cooked, combine barley, browned chicken, mushrooms, tomato puree, scallions, parsley flakes, salt, and pepper. 

Stuff each pepper half and top with a slice of cheese. 

Place in freezer containers, using wax paper or parchment to separate layers. 

To Cook (From Frozen)

Arrange frozen peppers in a single layer in a baking dish. Cover with foil and bake at 350 for 45 minutes. Remove foil and brown cheese topping for 5-10 minutes.