A Microwave Cooking Tray and Sleeve Assembly comprises a tray for holding food to be cooked, a transparent heat seal covering the tray, and a sleeve designed to hold the tray. In order to cook the food in the tray, the assembly is placed in a microwave oven. During cooking, side vents on the tray channel steam out of the tray. Holes in the sleeve allow the steam to easily escape the box after passing through the vents in the tray. After a short period of cooking in the microwave oven, the tray is removed from the sleeve, the heat seal is removed from the tray, and the food in the tray is ready to eat.