Preheat your oven to 325°F. Grease and flour a 9x5-inch loaf pan.
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
In a large mixing bowl, cream the softened butter and sugar together until light and fluffy, about 3-4 minutes.
Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
Gradually add the dry ingredients to the butter mixture, alternating with the buttermilk. Begin and end with the flour mixture, mixing until just combined.
Gently fold in the sliced strawberries, being careful not to overmix.
Pour the batter into the prepared loaf pan and smooth the top.
Bake for 60-70 minutes, or until a toothpick inserted into the center comes out clean.
Allow the cake to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.