Preheat the oven to 425 degrees. Coat a muffin pan with cooking spray.
Prepare the muffin batter by whisking together the white sugar, brown sugar, and eggs until well creamy and smooth.
Add the buttermilk, oil, and vanilla extract then whisk until smooth and creamy.
In a separate dish stir the flour, baking powder, and salt together until well combined.
Slowly add half of the flour mixture to the batter until just combined.
Gently fold in 1 ¼ cups of the raspberries being careful not to break them up. Pour the batter equally into the muffin pan filling them to the top. Add the remaining ¼ cup of raspberries to the top of each muffin.
Sprinkle some coarse sugar on top of each muffin.
Place into the oven and bake for 5 minutes. Reduce the heat to 350 degrees and continue to cook for 13-15 minutes, or until a tester inserted in the center comes out clean. Side Note: Starting the baking at a higher temperature the reducing it helps make the muffin dome.
Remove from the oven and cool in the pan for a few minutes before putting them on a wire rack over parchment paper to finish cooling. Serve and enjoy