Place beets in a baking dish, cover with foil and bake at 400°F for 2 hours. I cut my largest beet in half for even baking. Beets do not have to be fully cooked through. Once beets are cool enough to handle, use gloves and rub beets to remove the skin - it should come off easily. Grate beets on the large holes of a graterGrate carrots, slice bell pepper and chop onions and tomatoes.Put marinade ingredients into a large soup pot and bring marinade to a boil. Add all prepared vegetables including beets to the pot and simmer partially covered 50 min, stirring occasionally. Do not fully cover with lid since the vinegar needs to evaporate out as it cooks. When done, vegetables will be soft. Cool salad to room temperature then refrigerate until ready to serve.