Cover just the edges of the pie crust (the lip) with aluminum foil to brevent over browning.
Crack eggs into a large mixing bowl and add the milk, blend with an electric mixer on low speed for 1 minute, or beat with a whisk or fork for several minutes until well blended and uniform (The more thoroughly you mix this, the more fluffy and light this dish will be).
Take the frozen chopped spinach and the fresh broccoli and cut them finely or run through food processor until minced and then put into the bowl with the egg mixture.
Thinly slice dime sized slices of the asparagus.
Add asparagus, minced onions, and salt into the mixture and stir well and pour half of the mixture into each pie crust.
Bake the quiches in the oven for 35-45 minutes until center is solid.
Melt the cheddar cheese, either on the stive over low heat, or in the microwave after slicing it up.
Pour half the melted cheddar on each quiche.
Return the quiche to the oven and cook another 5-15 minutes, until quiche is cooked through and the cheese is slightly brown, to well browned, depending on your preference. We prefer barely browned and slightly liquid.
Slice into 1/8ths for one serving.
Variations- try other cheeses like swiss (traditional), herbed cheeses, provelone for a smoky flavor, or even gouda or edam. Other good ingredients to try may be bacon (we use vegetarian bacon, a few strips finely minced as it is a strong flavor), ham, etc.