Preheat the oven to 375°F. Grease a 9-inch pie plate very well.
In a medium skillet, melt the butter over medium heat. Add the broccoli and garlic powder, and cook until tender-crisp, about 4 to 5 minutes. Cool completely.
Meanwhile, whisk together eggs, cream, dry mustard, and salt.
Place the cooled broccoli in the prepared pie plate. Top with ¾ cup of cheddar cheese.
Pour the egg mixture over the broccoli. Sprinkle the top with the remaining cheddar cheese.
Bake uncovered for 35-40 minutes or until a knife inserted in the center comes out clean.
Cool 5 minutes before cutting.
Notes
Grease your pie plate well to prevent sticking.
Cook broccoli just to tender-crisp and cool completely.
Add an extra egg white for a fluffier quiche.
Do not overload with too many ingredients.
Do not overcook.
Allow quiche to cool and set for about 5 minutes before serving.