Preheat oven to 350 degrees. Grease and flour a bundt pan and set aside.
Cream butter in a stand mixer or food processor until smooth and a slightly lighter shade of yellow (about two minutes). Add sugar and continue to cream for three minutes. Then add eggs, one at a time, followed by sour cream, and vanilla extract and continue mixing until uniform.
1 pound butter, 1 ¾ cup granulated sugar, 6 eggs, 1 cup sour cream, 2 teaspoons vanilla extract
In another bowl, whisk together flour and sea salt. Add this dry mixture to creamed butter mixture in two batches and mix until just combined. Give the batter a few stirs by hand to make sure no dry pockets remain.
4 cups flour, ½ teaspoon fine sea salt
Add freeze-dried strawberries to a blender or food processor and pulse until ground into powder. Divide cake batter in half and mix ground strawberries into one half of the batter until it is a uniform bright pink color.
1 ½ ounces freeze-dried strawberries
Scoop batter into prepared pan, alternating between plain batter and strawberry batter. Once pan is about halfway full, use a butter knife to swirl the two batters together. Repeat with remaining batter.
Place pan on middle rack of oven and bake for about an hour and 20 minutes or until a toothpick inserted into multiple parts of the cake comes out clean.
Remove cake from oven and let it sit in pan for about 10 minutes then carefully invert it onto a plate to finish cooling to room temperature.