Select equal portions of fresh sweet potatoes, brussel sprouts, and beets.
Cut the brussel sprouts in half, peel the potatoes and cut into bite-sized pieces, cut beets as well.
Place top rack in oven just above center and the second rack a notch or two below for space to get a second pan in and preheat oven to 400 degrees.
Grease jelly roll pans with a light coat of spray. (Marsha had only two pans, and cooked the brussel sprouts first. Again, this is the beauty of a vegetable for a large group that doesn't have to be served hot.)
Spread each vegetable individually and evenly over pan.
Sprinkle olive oil semi-generously (although excess will not hurt) over the vegetable.
Sprinkle fresh ground black pepper and salt evenly over vegetables.
Top with three cloves each pan of chopped fresh garlic.
Chop fresh rosemary (about 3 long sprigs per pan) and sprinkle around pan.
Place pans in oven until bottom of vegetables are golden brown. The time varies depending on the veggie.