How to Roast Turkey in a Steam Oven (recipe and tips ... 5. Rub the steamed turkey all over with the softened butter, and put it back in the oven. Roast for 30 minutes, then brush all over with the glaze and continue roasting, brushing with more glaze every 15 minutes, until the thickest part of the bird, in the leg meat just next to the breast, reaches 73-76⁰C (163-169⁰F) on an instant read thermometer.