Preheat oven to 400 degrees. Line muffin tins with paper liners (or grease well if you don't have liners) & set aside.
In a medium bowl, whisk together flour, salt, baking powder, and cinnamon. Whisk in the sugar. In a separate medium bowl, mix canola oil, egg, milk, and vanilla together. Use a fork or whisk and combine well. Slowly incorporate the wet ingredients into the flour mixture, being sure to not overmix. The batter will be thick.
Carefully fold in the peaches.
In a small bowl, mix the cream cheese, sugar, and cinnamon together, until creamy and smooth. Fill each muffin cup halfway with batter. Next, add a small spoonful of cream cheese filling to each muffin cup. Cover the cream cheese filling with the remaining batter. Sprinkle each muffin with cinnamon and sugar.
Bake muffins for 17-20 minutes, or until muffins are golden brown and a toothpick comes out clean. Remove the muffins from the pan and let cool on a cooling rack.