* Eggs at room temperature: This is necessary only when eggs are to be combined with a fat and a sugar. Cold eggs could harden the fat in the recipe causing the batter to curdle and affecting the texture of the finished product. To bring eggs to room temperature, remove them from the refrigerator 20 to 30 minutes before baking or put them in a bowl of warm water for a few minutes while assembling other ingredients. * Separated: Yolks and whites are often separated, and beaten separately, particularly when aerating the whites is important. Egg yolks contain fat which will inhibit the foaming of the whites and prevent them from reaching their fullest possible volume. The yolks and whites must be separated very cleanly and bowls and beaters must be very clean. Eggs will separate more easily if cold, but the whites will absorb more air and beat faster and to a greater volume and stiffness if at room temperature. * Slightly beaten: Beat with a fork or a whisk just until blended. * Well beaten: Beat with a whisk or electric mixer until light, frothy and evenly coloured. * Beat yolks until thick and lemon-coloured: Beat yolks with a mixer for a few minutes until they become a pastel yellow colour and fall in ribbons when the beater is lifted or they are dropped from a spoon. * Beat egg whites until frothy or foamy: This is the first stage of beating whites, either by hand with a whisk or with a mixer. The whites will look cloudy and like froth or foam! * Beat egg whites until soft peaks form: Use an electric mixer or a whisk to beat whites until rounded peaks form. The whites will droop when the beater or whisk is removed. * Beat egg whites until stiff peaks form: Use an electric mixer or a whisk to beat whites until upright, pointed peaks form when the beater or whisk is removed. The peaks should be moist and glossy-looking and should not flow when the bowl is tipped or inverted. If the whites are underbeaten, the finished product will be heavier and less puffy than desired. If the whites are overbeaten, they may form clumps which are difficult to blend with other foods in the mixture and the finished product may be dry. * Add sugar gradually: Sugar is often beaten with the egg whites, a tablespoon at a time, when making meringues and some cakes. This helps to stabilize the foam. Since sugar can actually slow or prevent the foaming of the whites, it must slowly added so the finaly volume is not diminished. * Add cream of tartar: Beaten egg whites can be easily deflated if not stabilized. Cream of tartar or lemon juice are effective stabilizers. * Temper eggs: To prevent eggs from coagulating or cooking when combined with a hot mixture and forming lumps, they must first be warmed or tempered. Stir a little of the hot mixture into the beaten eggs, then stir the warmed egg mixture into the remaining hot mixture. * Cook until mixture coats the back of a spoon: Custard mixtures are cooked to proper doneness when a thin film of the mixture adheres to a metal spoon dipped into the custard. The custard should be slightly thickened but not set.