Strawberry Shortcake with Thyme and Whipped Cream

Name: Strawberry Shortcake with Thyme and Whipped Cream
Ingredients: 1 cup (2 sticks) unsalted butter; 8 large eggs; 1 3/4 cups sugar; 1/2 teaspoon kosher salt; 1 tablespoon thyme leaves; 1 teaspoon vanilla extract; 1 3/4 cups all-purpose flour, divided; 1/2 cup sugar; 6 thyme sprigs; 1 pound strawberries, hulled, halved or quartered if large, divided; 2 cups heavy cream; 1/2 cup sour cream; Baby strawberries (optional) and thyme sprigs (for serving); 2 (8-inch) springform pans, preferably light-colored