Toast and grind all spices. (To toast spices, place them over high heat in a small nonstick skillet on the stove. Toss them frequently until fragrant, about 2 minutes.)

Mix spices and soy sauce. Rub mixture over lobsters. Let them sit for 30 minutes. Meanwhile, preheat oven to 450° F.

Lay out lobsters on pans, such as roasting pans, Pyrex bakeware, or nonstick cookie sheets. Bake lobsters for 6 minutes.