In a large bowl, crack the eggs. Add the ricotta cheese, pinch of salt, cheddar cheese and onion. Mix well.
Add the flour, and baking powder, and mix well.
Line a 9x13 baking dish with parchment paper and pour in the egg mixture.
Spread the mixture out evenly with a spatula or the back of a spoon and bake for 20-30 minutes or until set (the eggs should not jiggle). A skewer/fork/toothpick should come out clean once inserted.