Spray the rack of a broiler pan with non-stick cooking spray. Arrange rumaki on rack and cook in a hot oven for approximately 30-40 minutes, turning once or twice to be sure bacon is crispy all over.
When done, remove to paper towels to drain for a few minutes before arranging on platter. I like to use a paper doily or two to line the platter, as it also will soak up some of the drippings. Arrange Rumaki into two sections, grouping those with liver together, and those with only water chestnuts or pineapple chunks together.