There's two cooking recipes that uses Sugar Beets, neither of which though are not that great, except maybe to help grind cooking. Both come from the
Traditional Russian Cuisine book which you can get at St.Petersburg at the craftsman shop with the 17th century 5th period through 18th 3rd period chrono titles
Red Turnip Salad Needs R6 cooking, 1 onion, 1 sugar beet, 1 carrot. Restores 35 vigour plus cures scurvy
Borscht? (Cant seem to find it) needs R11 cooking, 1 beef, 1 potato, 2 sugar beets. Restores 55 vigour plus fatigue