Preheat oven to 350°F. Butter a 9-inch springform pan and line the bottom with parchment paper.
Dice half the strawberries into small pieces. Slice the remaining half lengthwise.
Beat eggs and sugar on high speed for 5 minutes until thick, pale, and fluffy.
Mix in sour cream, oil, and vanilla until combined.
In a separate bowl, whisk together flour, baking powder, and salt.
Add the dry ingredients to the batter in three additions, folding gently until just combined. Do not overmix.
Pour half the batter into the prepared pan. Scatter the diced strawberries evenly over the top.
Add the remaining batter, then arrange the halved strawberries cut-side down across the surface, pressing them in slightly.
Bake for 45–55 minutes, or until a toothpick inserted in the center comes out clean.
Cool in the pan for 15–20 minutes before releasing the springform ring.
For the sauce, combine strawberries and sugar in a small saucepan over medium heat. Cook for 8–10 minutes, stirring occasionally, until the berries break down and the sauce thickens slightly.
Drizzle sauce over each slice before serving.