Step 1

Place a rack in middle of oven; preheat to 250°. Place strawberries in an 8x8" baking dish and toss with sugar and St-Germain. Roast, stirring every hour or so, until juicy and tender, 2½–3 hours. Let cool.Do Ahead: Strawberries can be roasted 1 week ahead. Transfer to an airtight container; cover and chill. Reheat in a small saucepan if desired.

Step 2

Place a rack in middle of oven; preheat to 325°. Butter and flour a 6-cup Bundt pan or 9x5" loaf pan. Whisk baking powder, salt, and 1½ cups flour in a medium bowl.

Step 3

Using an electric mixer, beat eggs, sugar, St-Germain, lemon zest, vanilla, and ¾ cup butter in a large bowl on medium-low speed until smooth and combined (use the paddle attachment if using a stand mixer), about 2 minutes (the mixture will look broken and that’s okay). Reduce speed to low and gradually beat in dry ingredients, ¼ cup at a time, scraping down the sides of bowl as needed, until combined. Increase speed to medium and beat in cream until incorporated.

Step 4

Scrape batter into prepared pan and smooth surface. Bake until golden brown and a tester comes out clean or with just a few crumbs, 40–45 minutes if using Bundt pan or 50–60 if using loaf pan. Transfer pan to a wire rack and let cake cool in pan 20 minutes.

Step 5

While the cake cools, cook butter in a small saucepan over medium-low heat, swirling often, until butter foams, then browns (do not burn) and smells nutty, 6–8 minutes. Add sugar and cook, whisking constantly, until dissolved, about 1 minute. Whisk in lemon juice and salt; cook, swirling occasionally, until mixture is reduced slightly, about 5 minutes. Add St-Germain and vanilla and cook, swirling often, until glaze is syrupy, about 2 minutes.

Step 6

Turn out cake onto a plate (flip cake upright if using a loaf pan). Poke holes all over cake with tester; spoon glaze over warm cake. Cut cake into slices and serve topped with roasted strawberries and their juices.