Rinse whole water chestnuts. Cut bacon strips in half. Wrap bacon around water chestnut and secure with toothpick. Place on cookie sheet and bake at 400°F until crisp.
In a sauce pan on the stovetop (or in a microwave) heat the ketchup and brown sugar mixture until bubbling.
Pat bacon wraps down with paper towel to remove excess grease and place in serving dish (corningware works well). Pour sauce over roll ups and serve.