These little crustless quiches are just right for entertaining, whether it's for brunch, a cocktail party, or as a starter course for a more formal dinner party. They make good use of leftover cooked chicken, or a rotisserie chicken that's bought just for this purpose, with spinach, watercress, and radishes and either kefir, soy milk creamer, or regular milk or cream in the custard base. Serve warm or at room temperature.