Add ham and cheese to a prebaked pie shell. Be sure to spread evenly over the crust. You want some ham and cheese in every bite.
In a medium mixing bowl, whisk together eggs, half-n-half, salt, pepper, ground mustard, and onion powder. Pour eggs mixture over ham and cheese.
Bake quiche for 35 to 40 minutes or until crust is browned and eggs are set.
Remove from oven and all to rest for 10 minutes before serving. Garnish with chives, if desired.
For the pie crust, you can use a homemade or store-bought crust. Just be sure to par-bake the crust for 10 to 15 minutes at 450 degrees F. Use foil and pie weights or dried beans to keep the sides of the crust from falling over during baking. You can par-bake your crust the day before to cut down on prep time in the morning.
Make Ahead: To make the ham and cheese quiche ahead of time, just keep your baked quiche in the fridge, covered in plastic wrap, until ready to serve. You can serve it cold or leave it out to come up to room temperature or place it in a 200 degree F oven to warm it up.
Storing leftovers: Keep your leftover quiche fresh by storing in an airtight container in the fridge for 2-3 days.
Freezing: Cover tightly with foil and place cooled, fully baked quiche in a plastic bag. Freeze for up to 4 months. Thaw in the fridge overnight and reheat in the oven.