A slice of broccoli cheddar quiche has about 350 calories. This number can change depending on the ingredients used and the size of the slice. A quiche is made up of an egg mixture, typically including milk and cream, that is baked in a pastry crust. The addition of broccoli and cheese adds more calories to the dish.
To reduce the calorie content of quiche, you can use low-fat milk and cheese, and a whole wheat pastry crust. You can also add more vegetables to the quiche, such as mushrooms or tomatoes. If you are trying to cut down on calories, you may want to consider eating only half a slice of quiche.