Keep the peel on the orange and cut into 3 wedges. Cut each wedge into small triangular slices, about 1/8-inch thick.

In a heavy flat skillet or stovetop grill pan, heat the olive oil over medium heat. Add the olives and orange wedges to the pan and shake back and forth to combine. Stir in the garlic. Continue to shake the pan back and forth or to gently stir the contents for about 5 minutes, until the olives are warmed through, the garlic soft and shiny, and the orange slices slightly wilted. Stir in the oregano and transfer to a bowl.

Grill, saute or toast slices of good bread. Place the olive-orange mixture on top and serve.