Preheat oven to 425°.
Pat artichokes dry with paper towels. Combine artichokes, salt, pepper, and garlic in a large bowl. Add spinach, cheese, and chicken; toss gently to combine.
Brush oil over a baking sheet; sprinkle with cornmeal. Unroll dough onto prepared baking sheet; cut into 6 equal portions. Cover and let rest 5 minutes. Pat each portion into a 6 x 5-inch rectangle. Spoon 2/3 cup spinach mixture into center of each dough portion. Fold one corner of each dough portion over spinach mixture to form a triangle. Press edges together with fingers to seal. Bake at 425° for 12 minutes or until golden.