Preheat oven to 250°.
Place bread in a food processor; pulse 10 times or until coarse crumbs measure 2/3 cup. Place breadcrumbs on a baking sheet. Bake at 250° for 30 minutes or until dry.
Heat olive oil in a large nonstick skillet over medium heat. Add minced garlic, and cook 30 seconds, stirring constantly. Remove garlic mixture from heat, and let stand 5 minutes. Return pan to heat. Stir in breadcrumbs; cook 6 minutes or until lightly browned, stirring mixture frequently.
Cook the fettuccine according to package directions, omitting salt and fat; drain. Place fettuccine in a large bowl. Add the breadcrumb mixture, parsley, Gorgonzola, walnuts, lemon juice, salt, and black pepper; toss gently to combine. Serve immediately.