Preheat oven to 350 degrees. Line standard muffin tins with paper liners. Whisk dry ingredients in a large bowl. Cream butter and sugar with a mixer until light and fluffy. Add eggs, 1 at a time, beating after each addition.
Reduce speed to low. Mix milk and vanilla in a bowl. Add dry ingredients to butter mixture in 3 additions, alternating with milk mixture and ending with dry ingredients. Stir chopped strawberries into batter. Scrape sides of bowl. Divide batter among muffin cups, filling each 2/3 full.
Bake cupcakes until testers inserted into centers come out clean, about 20 minutes. Let cool in tins on wire racks. Once cupcakes are cool, frost tops with Strawberry Buttercream. Frosted cupcakes will keep, covered and refrigerated, for up to 2 days. Top with a strawberry just before serving.