Place your oven rack in the centre position and pre-heat the oven to 425.
In a mixing bowl, stir together the artichoke hearts, spinach, mayonnaise, sour cream, lemon zest and juice, the pine nuts, black pepper, salt, and 1/2 cup of the parmigiano cheese.
Rub the inside of a small baking dish with the crushed garlic, then discard the clove. Pour the mixture into the dish and spread top an even thickness, sprinkle the top with the remained 1/4 cup of parmigiano and the crumbled feta.
Bake until the top browns and the dip heats through, about 20-30 minutes. Remove from the oven and let cool slightly before serving with pita chips, or the crackers of your choice.