In a medium-large bowl, combine marmalade, 2 tablespoons of the olive oil, chipotle powder, and cumin. Add turkey pieces and fold to combine.

Add onion pieces to a small-medium bowl and drizzle with remaining tablespoon of olive oil. Fold to coat evenly.

Add turkey, onion, and thin orange slices to skewers, alternating between each one. When adding the orange slice, fold each half-round in half, sandwiching it between the other pieces. Sprinkle finished kebabs with salt and black pepper, to taste.

Heat grill to medium to medium-high heat, about 425° F. Make sure grates are scrubbed clean and then oiled. (To oil the grates, add some cooking oil to a small bowl. Then fold a heavy paper towel a few times to make a smaller square. With a tongs, grasp the folded paper towel and dip it into the oil until the paper towel is drenched. Then run the paper towel over the grates, repeating until all grill grates are thoroughly oiled.)

Place turkey kebabs on hot grill grates and let cook for 4 to 5 minutes, until beautifully charred. Turn the kebabs over and continue to cook for another 4 to 5 minutes. If your turkey pieces are larger or smaller, cook time will vary accordingly. Place cut sides of orange halves on clean, hot grill grates and cook until charred. Be careful to not move the oranges around too soon or you will risk tearing the orange flesh without attaining a char. Remove turkey kebabs and orange pieces to serving platter and serve hot.

Squeeze grilled orange over kebabs right before eating.