Preheat oven to 350 degrees. Brush four 3-by-6-inch loaf pans with butter; set aside. In a small saucepan, cook cranberries and 2 Tbsp sugar over medium heat, stirring, until cranberries begin to pop, about 6 minutes. Pour among pans, evenly covering bottoms with cranberries.
In a small bowl, whisk together almonds, baking soda, and salt. In a medium bowl, beat butter and remaining sugar until pale and fluffy. Add eggs, one at a time, beating well after each, and vanilla. Add almond mixture and stir until combined.
Pour batter over cranberries into pans and gently smooth tops with an offset spatula. Place pans on a rimmed baking sheet and bake until loaves are golden brown and a tester inserted into centers comes out clean, about 30 minutes. Let cool slightly, then run an offset spatula around the edges of the pans and invert cakes onto a wire rack, cranberry side up.
Cakes are best given the day they're made.