Unlike some vegetables, you can't just go tossing artichokes straight on the grill. They require a few simple prep steps before ever hitting the grates to ensure a tender smoky bite from start to finish.
Prep the artichokes by cutting off the tips of the leaves and any little thorns with kitchen scissors. Slice about 3/4 inch to an inch off the tip of the artichoke with a serrated bread knife. Pull off any smaller leaves towards the base and on the stem. Cut off the excess stem, leaving about a 1-inch stem on the artichokes. Rinse the artichokes in running cold water gently working your fingers into the petals of the artichoke to loosen and open them up a bit.
Place a small amount of water in a large pot for steaming. Add a cut-up lemon and 3 whole garlic cloves that have been crushed into the water. Bring to a boil.
Place a steamer basket in the pot and add the artichokes top down. So that the trimmed pieces are facing downward and the stem is facing up. Steam for 25-35 minutes or longer, until the outer leaves can easily be pulled off.
Remove the cooked artichokes and cut them in half. Scoop out the rough fibers from the center of each half.
Grill the artichoke
Preheat the grill to medium-high.Brush each steamed artichoke half with a bit of olive oil and place face down on a hot grill for about 5 minutes
Make the Zesty Garlic Aioli
Combine mayo and sour cream. Add the zest and juice of one lemon and 3 minced garlic cloves. Season with salt and pepper.