Preheat oven to 350°F/180C, place a 10-inch cast-iron skillet in the oven, let skillet preheat in the oven for about 10 minutes.
Whisk together flour, cornmeal, and salt in a small bowl until combined, set aside.
Add the butter and sugar in the bowl of a stand mixer fitted with the whisk attachment, beat on high speed, stopping occasionally to scrape down sides of bowl. Beat until the butter and sugar are pale and fluffy, about 4 minutes total.
With the mixer on medium-low speed, add eggs, 1 at a time, beating well after each addition.
Next, add in the goat cheese, beat until combined, about 30 seconds.
Add buttermilk and vanilla/s, beating until just combined, about 1 minute.
Gradually add the flour mixture, beating until just combined, about 1 minute.
Carefully remove hot skillet from oven, adding 1 tablespoon butter. Swirl skillet until butter is melted and evenly distributed across the bottom of the pan. Pour cake batter in the hot skillet, smoothing the batter for an even distribution. Arrange strawberries and rhubarb in an even layer on batter, sprinkle with turbinado sugar.
Bake in preheated oven until a wooden pick inserted into center of cake comes out clean, 55-60 minutes. Let cool slightly on a wire rack for 20 minutes.
While the cake is cooling it is time to whip up the chilled rosemary infused cream.
Serve cake warm with a dollop of rosemary whipped cream.