Preheat oven to 350ºF/180ºC. Grease a muffin pan or line with muffin liners. Set aside.
In a large bowl whisk together flour, baking powder, and cinnamon. Set aside.
In a medium bowl whisk together eggs and sugar until well combined. whisk in melted butter, heavy cream, and vanilla extract until combined. Add this to the flour mixture and mix until just combined. Don't overmix. Stir in Peaches.