Preheat the oven to 350°F (175°C). Grease and flour a 9-inch round cake pan.
In a bowl, whisk together the flour, baking powder, baking soda, and salt.
In a separate bowl, beat the butter and sugar until light and fluffy. Add the eggs, one at a time, and mix well. Stir in the vanilla extract.
Gradually mix the dry ingredients into the wet ingredients, alternating with the buttermilk, starting and ending with the flour mixture. Fold in the diced strawberries.
Pour the batter into the prepared cake pan and smooth the top. Bake for 30-35 minutes or until a toothpick inserted into the center comes out clean.
Let the cake cool in the pan for 10 minutes, then remove it from the pan and let it cool completely on a wire rack before serving.
Notes
For an extra touch, top the cooled cake with whipped cream and fresh strawberry slices.