A jar of roasted red peppers gets blended into a tangy sauce for a frittata that’s filled with chopped artichoke hearts and mushrooms. For the prettiest presentation, serve right away—the artichokes and mushrooms may discolor the frittata base over time (even though the frittata will still taste as good).
1. Preheat oven to 400°F. Slice artichoke hearts lengthwise into 1/4-inch slices. Set aside.
2. Coat large ovenproof nonstick skillet with cooking spray, and add 1 Tbs. reserved oil from artichokes. Heat skillet over medium-high heat. Add mushrooms, onion, and 1/4 tsp. salt; sauté 5 to 7 minutes, or until mushrooms are browned. Add artichokes, and cook 1 to 2 minutes, or until heated through.
3. Whisk together eggs, egg whites, and tarragon, and season with remaining 1/2 tsp. salt and pepper. Pour egg mixture into pan, rearranging artichokes and mushrooms, if necessary. Cook 3 minutes, or until frittata bottom is set.
4. Transfer skillet to oven, and bake 8 minutes, or until frittata is set in center.
5. Meanwhile, purée red peppers in food processor until smooth.
6. Using heat-proof spatula, loosen frittata from skillet. Slide frittata out onto platter. Cut into 4 wedges. Serve each wedge with 1 Tbs. red pepper purée.