Set potatoes on a cookie sheet and drizzle them with just enough oil to lightly coat them, about 1 1/2 tablespoons. Toss potatoes with cumin seed and roast 20 minutes at 400 F in a hot oven, then broil 5 minutes on high to brown edges of the cut potatoes. If you are making them with the Grilled Boneless Leg of Lamb, set the baking sheet with the potatoes in the oven along side the lamb on the same rack. Toss cooked potatoes with salt, to your taste, and serve.