In a microwave, heating is stronger in the outer parts of the food; that is why food is arranged in a ring on the plate with the center left empty. Place thick, dense pieces near the outer edge and thin pieces that heat quickly toward the center. Set the plate near the edge of the turntable rather than directly in the middle, stir halfway through heating, and let it stand for one or two minutes at the end.
Microwave radiation reaches the plate from all directions, but the energy that reaches the center is lower than at the edges, and the food in the middle gets heat only from neighboring layers. That is why food piled in the center of a plate is the last area to heat. When food is arranged in a ring with the center left empty, every piece has a side facing outward and heating becomes noticeably more even. For the same reason, ring-shaped microwave pans are available. Leaving the center of the plate empty also shortens the heating time. As heating becomes more even, the standing time is shortened too.
Arrange the pieces by position too. Put thick, dense, cold pieces, such as slices of meat, potatoes, and large meatballs, along the outer edge of the plate. Move thin, moist pieces that heat quickly, such as vegetables or sauce, toward the center. If you are heating different foods together, evening out their height also helps; spread out any piled-up section. With bone-in pieces, heat travels differently through the bone, so heating will be more even if the meat can be separated from the bone. The same rule applies when thawing frozen food.
The plate’s position is another detail. In ovens with a turntable, placing the plate directly in the center reduces the benefit of rotation; position the plate off-center. If the turntable does not rotate or the microwave is used without a turntable, manually turn the plate 180° halfway through heating. The plate should not touch the oven walls. If heating 2 containers at once, arrange them with space between them around the turntable rather than side by side, and extend the time. Follow the oven’s own manual if it recommends a different placement.
Covering and stirring complete the arrangement. Cover the top of the dish with a microwave-safe lid or paper towel; this keeps steam inside, prevents the food from drying out, and reduces splattering. Do not seal the lid airtight. Stir liquid dishes and soups halfway through heating; stirring is the quickest way to even out hot and cold spots manually. For solid foods, change the position of the pieces: move the ones at the edge toward the center and the ones in the center toward the edge. Do not fill a container more than halfway for liquid foods such as soup.
The result still settles while standing. After heating, let the food stand in its dish for one or two minutes; the heat evens out inside during this time. When reheating leftovers, every part needs to reach 74°C / 165°F; check this with a thermometer in several places, including the thickest part. If any area is below 74°C / 165°F, stir the food and heat it for 1 more short cycle. Keep each cycle short; 1 long cycle dries out the edges and spoils the texture. Use oven mitts when removing the plate, since its edges may be hot.