Gather all your ingredients.

Grease a large bowl with olive oil.

Combine all-purpose flour, spelt flour, yeast, and kosher salt in the bowl of a stand mixer fitted with a dough hook. Add water and knead until dough is smooth, elastic, wet, and sticky, about 5 minutes. Transfer dough to the prepared bowl. Cover and let rise on the counter for 30 minutes.

Uncover the dough. Wet one hand and grab one side of the dough in the bowl. Pull it up slightly and fold it in towards the center. Repeat this folding technique 6 or 7 more times, turning the bowl slightly in between each fold. Cover and let rest for 30 minutes.

Repeat the folding and resting process two more times, for a total of 2 hours of resting.

Repeat folding once more. Cover and place in the refrigerator for 12 to 24 hours.

When ready to bake, line a sheet pan with a silicone liner; sprinkle some flour on the liner.

Transfer dough to a lightly floured surface and pat or press it into an oval shape, flouring lightly as necessary. Cut the oval in half lengthwise into two equal portions.

Shape fougasse: On one piece of dough, fold one end in over the center third, then fold the other end in over top to resemble a triangle. Transfer to the prepared pan and repeat with the second piece of dough.

Cover both triangles with an oiled piece of plastic wrap and let sit until dough warms up, 30 minutes to 1 hour.

Line two baking sheets with parchment paper; generously sprinkle cornmeal on the parchment. Remove plastic from the dough.

Transfer one piece of dough to a lightly floured surface. Shape and cut the dough to resemble a leaf using a pizza wheel. Pull dough gently apart to create openings. Repeat with second dough piece.

Preheat the oven to 450°F (230°C). Brush one fougasse with olive oil; sprinkle coarse sea salt.

Bake one fougasse in the center of the oven for about 20 minutes or until golden brown. Let cool on a rack.

Repeat the baking process with the second fougasse.