Preheat broiler. Cut bell peppers in half lengthwise, discarding the seeds and membranes. Place the pepper halves, skin sides up, on a foil-lined baking sheet, and flatten with hand. Broil 15 minutes or until blackened. Place in a large zip-top plastic bag; seal. Let stand 15 minutes. Peel and cut into 1/2-inch strips.
Combine the shrimp, 2 teaspoons Lemon Grass Oil, crushed red pepper, and minced garlic in a large zip-top plastic bag; seal and marinate in refrigerator 30 minutes. Heat a large nonstick skillet coated with cooking spray over medium-high heat. Add the shrimp mixture, and sauté for 1 1/2 minutes on each side. Remove shrimp from skillet. Heat 1 teaspoon Lemon Grass Oil in skillet, and add spinach. Cook spinach 1 minute or until spinach wilts, stirring frequently. Place spinach in center of each of 4 plates, and top evenly with bell peppers and shrimp.