Gala Apple is a sprawling Slavic supermarket housed in a former Rite Aid, located along the southern border of Kensington, Brooklyn. It’s loaded with odd food gems like these cute, 8 oz. “Subway Series” rye mini-loaves ($1.29), above, that come from a Queens bakery. Part of the baker’s profits benefit education about the Armenian Genocide. Just past the bread aisle, a refrigerated case is stocked with Russian cheeses and odd, layered dessert concoctions. Sausages......