Dice the peaches into 1/2-inch pieces and set aside. In a medium bowl, whisk together the flour, baking powder, baking soda, cinnamon, salt, and granulated sugar. This dry mixture can be prepared while your waffle iron preheats, maximizing efficiency.

In a large bowl, whisk together the milk, Greek yogurt, eggs, melted butter, and vanilla extract until smooth and fully combined. While doing this, preheat your waffle iron to medium-high heat—aim for a setting that produces golden-brown waffles, typically around 375-400°F if your iron has temperature controls. I like to let the waffle iron heat for about 3-4 minutes to ensure it's properly hot before cooking.

Pour the wet ingredient mixture from Step 2 into the bowl with the dry ingredient mixture from Step 1. Gently fold them together with a spatula until just combined—the batter should be slightly lumpy, not overmixed, which keeps the waffles tender. Fold in 1/2 to 3/4 cup of the diced peaches, reserving any remaining peaches for topping if desired.

Lightly grease the preheated waffle iron with butter or cooking spray. Pour the batter into the iron (amount depends on your waffle iron size—usually 1/2 to 3/4 cup per waffle) and close the lid. Cook until the waffles are golden brown and crispy on the outside, typically 4-6 minutes depending on your iron. I recommend cooking until steam stops releasing from the sides—that's usually a reliable sign they're done. Transfer finished waffles to a plate or cooling rack to keep them crispy while you finish the batch.

Arrange the cooked waffles on serving plates and top generously with homemade whipped cream and peach syrup. Serve immediately while the waffles are still warm and crispy.