Start by making the biscuits. Preheat oven to 450 degrees F and set out a small rimmed baking sheet.

In a large mixing bowl, combine flours, baking powder and soda, 2 tablespoons sugar, and sea salt. Dot the butter over the surface, and quickly rub into flour with fingertips until it's incorporated well and in pea-sized chunks. Fold in the buttermilk, flipping the dough several times to incorporate.

Turn out onto a lightly floured sheet of parchment. Knead dough into an oval. Pat dough out into a rough rectangle. Cut biscuits with a 3-inch high-sided biscuit cutter and arrange on a small un-greased baking sheet. Gather dough up a second time and cut out remaining biscuits. Any dough gathered a third time will be overworked and will yield an inferior shape – so on the second pass, try to create a shape that will accommodate the most biscuits. Sprinkle biscuits with remaining sugar; press lightly into the surface.

While biscuits cool, prep the strawberries. Toss 1 cup strawberries with half the sugar and macerate thoroughly with a fork. Toss with remaining berries, sugar, and thyme and set aside at room temperature.

To make the buttermilk whipped cream, beat cream with a whisk in your largest mixing bowl. When the cream forms soft peaks, fold in buttermilk and sugar, and whip until cream just passes soft peaks, it should be pillowy, but still holds its shape.

Carefully slice biscuits in half. Top the bottom half with strawberries, a generous dollop of cream, and a small sprig thyme. Top with biscuit top. Serve immediately.