1. Preheat oven to 375 degrees. Wash and dry swiss chard. Cut off the very ends of the stems. Roughly chop (leaving stems intact) the chard.
2. Add onion and Chard to the oil and saute until stems are tender (do not overcook). Add salt & pepper to taste.
3. Meanwhile, grate 2.5 cups of cheese. Use whatever varieties you want/have. Be creative! I used Swiss, Cheddar, Parmesan, and Cojito.
4. Wisk eggs. Add milk and cheese. Fold in the onion/chard mixture. Add salt & pepper to taste, if necessary.
5. Pour into a pie dish that has been sprayed with nonstick cooking spray.
6. Bake for 35-45 minutes or until golden brown and no liquid seeps when you poke it with a knife.