To make the batter, add the waffle mix to a large mixing bowl. Add in the water and oil, and mix until there are no more lumps. Let the batter rest for about 5 minutes, and preheat your waffle iron.
Add the oil to a skillet and bring it up to medium heat. Toss in the diced ham, and cook for a few minutes, just until it gets slightly crisp. Remove with a slotted spoon onto a paper towel to drain any remains of oil.
Once the iron is hot, spray cooking spray on the grates, then ladle in enough of the waffle batter to fill in the base of the waffle iron. Sprinkle with the ham, then the cheese, then ladle just a bit more batter onto the top. Close and seal the iron, give it a turn, and cook for about 4 minutes. Turn again, and continue to cook for a couple of more minutes, or until the waffle is a golden brown.
Remove the waffle, and slice your waffle. Repeat with the remaining waffles. Sprinkle with a bit of powdered sugar.
Repeat with remaining batter. You can keep the waffles warm and for the most part crisp and fluffy in a preheated 225 oven while you repeat the process.