Preheat oven to 400 degrees F. In a small saucepan combine butter, oil, and garlic. Cook over medium heat until butter melts. Remove from heat.
Brush butter mixture lightly over both sides of bread slices. Arrange bread slices in a single layer on a large baking sheet. Bake for 6 to 8 minutes or until golden. Top each slice with a half slice of Canadian bacon. Combine the mozzarella and Parmigiano-Reggiano cheese; sprinkle cheese over bacon slices.
Return slices to oven for 5 to 6 minutes more or until cheese is melted and bubbly. If desired, top with peach preserves while toasts are still warm.