Prepare the grill for direct heat cooking. If using a gas grill, set to medium heat.
To grill the peaches: Halve and pit the peaches, and then slice into wedges. Alternatively, slice into wedges while removing the pit. Brush each peach wedge with olive oil
Place the wedges on the grill and cook for 3 minutes per side, or until desired char marks. Flip and grill the other side for 3 additional minutes. Remove.
Grill baguette slices: Brush top of slices with olive oil. Place baguette slices on the grill over direct heat and cook 1-2 minutes per side, or until toasted and grill marks appear. Remove.
Assemble the crostini: Layer the grilled baguette slices with approximately 1 teaspoon of mascarpone, a grilled peach slice, a drizzle of honey, a small drizzle (less than 1/4 teaspoon) of aged balsamic, then top with a pinch of fresh mint.
Smoked honey: We love using smoked honey for this (made similar this recipe, but before incorporating it with butter), but you can use whatever honey you have lying around.