As a large restaurant chain, Howard Johnson’s relied on a commissary system of centralized kitchens. The clams would have been prepared as strips by the supplier, but here the whole clam body is fried. Individual recipes of this size were adaptations for family cooks, but nevertheless, the result is an authentic evocation of the chain’s most famous dish.
Combine evaporated milk and whole milk, egg, vanilla, salt, and pepper. Soak clams in liquid and then dredge in combination of cake flour and cornmeal, fluffing them in the flour mixture for light but thorough coverage. Shake off excess flour and fry in oil. Serve with French-fried potatoes, tartar sauce, homemade rolls, and butter.
From Anthony Mitchell Sammarco's A History of Howard Johnson’s: How a Massachusetts Soda Fountain Became an American Icon (Charleston, SC: The History Press, 2013).