Place garlic, avocado, olive oil, basil, salt, lemon juice, and water in a mini food processor or blender. Process until the aioli is very smooth. If it is too thick, add more water. Set aside.
Brush the flat side of each peach half with avocado oil.
Carefully place peaches flat side down on the grill. Cook for only 1-2 minutes, just long enough for them to get grill marks, and to warm through.
Serve with a judicious drizzle of aioli. (Too much will overpower the peaches.) Serve the rest of the aioli at table for adding to grilled meats, etc.
Recipe by Autoimmune Wellness at https://autoimmunewellness.com/grilled-peaches-with-basil-aioli/