For the Lemon Pound Cake:

1. Preheat the Oven: Preheat your oven to 350°F (175°C). Grease and flour a loaf pan (9×5 inches) or line it with parchment paper.
2. Mix Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.
3. Cream Butter and Sugar: In a large mixing bowl, beat the softened butter and sugar together until light and fluffy (about 3-4 minutes).
4. Add the Eggs: Add the eggs, one at a time, beating well after each addition.
5. Add Lemon and Vanilla: Stir in the sour cream, fresh lemon juice, lemon zest, and vanilla extract.
6. Combine Wet and Dry Ingredients: Gradually add the dry ingredients to the wet ingredients, mixing just until combined. Do not overmix.
7. Bake the Pound Cake: Pour the batter into the prepared loaf pan and smooth the top. Bake for 55-65 minutes, or until a toothpick inserted into the center comes out clean. Let the cake cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.

For Grilling the Pound Cake:

1. Grill the Cake: Once the pound cake has cooled, cut it into 1-inch thick slices. Preheat your grill or grill pan to medium heat.
2. Brush with Butter: Lightly brush both sides of each cake slice with melted butter.
3. Grill: Place the cake slices on the grill and cook for 1-2 minutes on each side, until grill marks form and the cake is lightly golden brown.

For the Topping:

1. Prepare Raspberries: In a small bowl, gently toss the fresh raspberries with 1 tablespoon of powdered sugar to slightly sweeten them.
2. Assemble the Dessert: Arrange the grilled lemon pound cake slices on serving plates. Top with fresh raspberries and a dusting of powdered sugar. Serve immediately.