Heat the oven to 350°F (175°C). Grease two 8-inch round cake pans, line the bottoms with parchment, and lightly flour the sides.

Purée the chopped strawberries in a blender or food processor. Simmer the purée in a small saucepan over medium heat for 10–15 minutes, stirring frequently, until reduced to about 1 cup; cool completely.

Whisk together the flour, baking powder, baking soda, and salt in a medium bowl.

Beat the softened butter and granulated sugar for 3–4 minutes, until pale and fluffy. Add the eggs one at a time, beating well after each addition, then mix in the vanilla.

Add the dry ingredients in three additions, alternating with the buttermilk in two additions. Mix just until combined, then fold in the cooled strawberry reduction and optional food coloring without overmixing.

Divide the batter evenly between the prepared pans. Bake for 28–35 minutes, until the centers spring back lightly and a toothpick comes out with a few moist crumbs.

Cool the cakes in their pans for 10–15 minutes, then turn them out onto wire racks. Cool completely before frosting.

Beat the cream cheese and butter until smooth. Gradually beat in the powdered sugar, then add the vanilla and salt; add cream or milk only as needed for a spreadable consistency.

Place one cake layer on a serving plate and spread it with frosting. Add the second layer, then frost the top and sides before slicing and serving.