Preheat oven to 350 degrees. Grease a 9-inch springform pan with butter; set aside.

In a large mixing bowl, use a handheld mixer to beat together the sugar and butter until well combined. Add in the drained ricotta and blend until light and fluffy; about 4-5 minutes.

Mix in the eggs, one at a time, beating after each addition. Add in the vanilla, baking soda, and salt, and mix until combined. Add in the flour and mix until the mixture is just combined. Use a rubber spatula to scrape down the sides of the bowl and fully incorporate the ingredients.

Fold in about three quarters of the raspberries into the batter. Pour the batter into the springform pan. Sprinkle on remaining raspberries.

Bake for 70-75 minutes. You will know the cake is done when the sides pull away from the edges of the pan and the top is golden brown. Always test for doneness using a toothpick inserted in the middle of the cake; the toothpick will come out clean when the cake is ready to take out of the oven.

Let the cake cool in the pan for 15 minutes before removing the collar of the pan. To remove the base, use a butter knife to loosen the bottom then slide the cake off using a spatula. Once the cake is cool, dust the top with powdered sugar before serving.