Step 1: Preheat your grill to medium-high heat and ensure the grates are clean and lightly oiled to prevent sticking, which is crucial for all grilled nectarine recipes.
Step 2: In a small bowl, whisk together 2 tablespoons of honey and the fresh lime juice to create the glaze.
Step 3: Brush the cut sides of the nectarine halves generously with the honey-lime mixture.
Step 4: Place the nectarines cut-side down on the hot grill. Close the lid and cook for 3-4 minutes without moving them until charred grill marks appear.
Step 5: Carefully flip the nectarines and cook for another 1-2 minutes until the fruit is heated through and slightly softened.
Step 6: While the fruit is grilling, whisk the mascarpone, the remaining 1 tablespoon of honey, vanilla extract, and lime zest in a small bowl until smooth and fluffy.
Step 7: Remove nectarines from the grill and place two halves on each serving plate. Top with a dollop of the vanilla mascarpone, garnish with fresh mint and pistachios, and serve immediately.