Nectarines and Peaches with Lavender Syrup

Preheat oven to 350°F. Toast pecans on a rimmed baking sheet, stirring once, until slightly darkened in color and fragrant, 10–12 minutes. Let cool.
Meanwhile, bring honey, 2 Tbsp. sugar, and 3 Tbsp. water to a simmer in a small saucepan over medium-high heat, swirling occasionally until sugar is dissolved. Add rosemary and lavender and remove from heat. Let sit 5 minutes. Remove rosemary and let syrup cool.
Bring a pinch of salt, remaining 1/4 cup sugar, and 1 Tbsp. water to a boil in another small saucepan, stirring to dissolve sugar. Cook (without stirring) until sugar turns a light amber color, about 2 minutes. Add pecans and cook, stirring constantly, until nuts are coated and caramel is a dark amber color, about 2 minutes. Immediately scrape out onto a parchment-lined baking sheet and spread out into a single layer; let cool. Break into smaller pieces.
Toss nectarines, peaches, lemon zest, and 1/4 cup syrup in a large bowl to coat. Let sit 5 minutes. Gently toss in half of Gorgonzola and half of candied pecans; taste and season with salt if needed. Transfer to a platter. Top with remaining Gorgonzola and candied pecans.
Syrup can be made 1 month ahead; cover and chill. Pecans can be candied 1 day ahead; store airtight at room temperature.