Mix all the ingredients together in a saucepan, excluding the peaches and house seasoning; simmer over medium heat for 15 to 20 minutes.
While the sauce is simmering, puree 2 cups of canned peaches or fresh peaches. Once the sauce is cooked, add the pureed peaches to the sauce and stir together.
Preheat the grill to medium heat, season the tilapia with the house seasoning. cook the fish on each side for 3 to 4 minutes. During the last few minutes of cooking, brush the fish with barbeque sauce.
Once cooked and plated, spoon some of the peach barbeque sauce on top of the fish.