Arrange the seasoned ribs on the Ninja Woodfire grill grate, stacking as needed.
Set the Ninja Woodfire to Smoker at 250°F (121°C).
Smoke until the ribs reach approximately 165°F internal temperature, checking about every hour.
Make the Smoked Peach BBQ Sauce
Melt the Butter in a saucepan over medium heat.
Add the White Onion and cook for 5 to 6 minutes until softened.
Add the Garlic and cook for about 30 seconds.
Stir in the Brown Sugar, Smoked Paprika, Granulated Onion, Granulated Garlic, White Pepper, Kosher Salt, and MSG.
Add a little Peach Nectar to help dissolve the sugar.
Stir in the Smoked Peaches, remaining Peach Nectar, Apple Cider Vinegar, and Ketchup.
Simmer over low heat for 20 to 30 minutes.
Blend until completely smooth using an immersion blender or countertop blender.
Taste and adjust with additional Brown Sugar for sweetness or Apple Cider Vinegar for extra tang, if desired.