Roast Peaches: Preheat the oven to 400°F (204°C) with a rack in the center position. Line a half sheet pan with parchment paper. Toss the peach wedges with the 1 tablespoon of maple syrup and spread evenly on the pan. Roast for 15 to 20 minutes, tossing halfway through or until lightly caramelized and fragrant. Remove and allow to cool on a rack as you prepare the waffles.
Prepare Waffles: As the peaches are roasting, prepare the waffle batter. In a large mixing bowl, whisk together the whole wheat pastry flour, unbleached all-purpose flour, sugar, baking powder, baking soda, and salt. In a separate bowl, whisk together the eggs, buttermilk, and melted butter until smooth.
Add the wet ingredients to the dry ingredients and whisk until the flour has just been asborbed and no large lumps remain. Don't overmix. Allow the batter to sit for 10 minutes. Preheat your waffle maker and lightly grease the plates with baking spray.
Pour the batter into your waffle maker (depending on the size and brand of your waffle maker, this amount will vary) and cook according to the manufacturer’s directions or desired texture. I prefer medium-low heat to get them a little crispy on the outside, but still soft and fluffy on the inside.
Prepare Vanilla Mascarpone: Combine the mascarpone cheese, maple syrup, vanilla extract, and salt in a medium bowl. Whisk together, and whip mixture by hand until it thickens slightly.
Assembly: Top the warm waffles with a roasted peaches and a large spoonful of whipped vanilla mascarpone. Dust with powdered sugar and serve with warm maple syrup. Serve immediately.