There are few summer treats as creamy and nostalgic as the milkshake. It’s as simple as blending some cold, sweet dairy into a drinkable consistency, but picturing a milkshake immediately invokes images of American diners in the 1950s, hot summer days, and childhood freedom. A milkshake is somehow simultaneously a dessert, a drink on the side, and a full meal if you choose. But one of the most agonizing choices can be picking which milkshake to make or order, and this guide is here to help.