In a medium bowl, whisk together the flour, sugar, baking powder and salt. Set aside.

In a large measuring cup or small bowl, combine the water and vinegar. Set aside.

Toss the pieces of butter into the flour mixture to coat. Then use a pastry blender (or dough scraper) to cut the butter into the flour. You should have various-sized pieces of butter ranging from coarse, sandy patches to flat, shaggy pieces to pea-sized chunks, with some larger bits as well. 

Drizzle in about half of the ice water mixture then stir lightly with a fork until the flour is evenly moistened and the dough starts to come together. If the dough seems dry, add a little more ice water –– 1 to 2 tablespoons (15 to 30 grams) at a time. 

Tip: The dough will still look a bit shaggy at this point. If you grab a small piece of dough and press it lightly with your hand, it should mostly hold together.

Dump the dough onto an unfloured work surface and form into a tight mound. Using the heel of your hand, smear the dough a little bit at a time, pushing it away from you and working your way down the mass of dough to create flat layers. Next, gather the dough back together with your scraper, layering the clumps of dough on top of one another. Repeat the process once or twice more; the dough should be cohesive and still have some big pieces of butter visible.

Shape the dough into a disk and flatten it (about 8 inches or 20 cm round). Wrap the disk in plastic wrap and refrigerate for at least 1 hour or overnight to rest.

Fire up your Ooni pizza oven and aim for 900°F (482°C) on the stone inside (about 20-30 minutes). You can check the temperature quickly and easily with your infrared thermometer.

Grease your cast-iron skillet with 2 tablespoons (28 grams) of olive oil.

Lightly flour your  work surface and rolling pin then roll the dough into a 14-inch (36 cm) circle and place it in the cast-iron skillet –– it will hang over the edges of the pan for now. Set in the refrigerator while you make the filling.

In a medium saucepan, melt the butter over low heat. Add the brown sugar and corn syrup and stir until the sugar is dissolved. Next add the orange zest and salt then whisk in the eggs until everything is well-mixed then fold in the pecans. Remove from heat, stir in the vanilla and (optional) bourbon, and let cool slightly, about 10 minutes.

Pour the filling into the center of the chilled dough, leaving a 3-inch (8 cm) border all around. Gently fold the edges of the dough up and over the filling to create loose pleats, leaving an opening in the center of the galette no larger than 6 inches (15 cm). Brush the edges of the dough with the heavy cream and sprinkle all over with the granulated sugar. When you’re ready to bake, turn the flame off in your oven. Place the cast-iron skillet in the center of the oven and close the door. Halfway through (at the 7-minute mark), rotate 180 degrees, then bake for another 7-8 minutes, or until the crust is golden and the juices are bubbling.

Tip: If you’re cooking with an oven that doesn’t have a door (Koda 12 and 16), simply turn off the flame. The oven will still retain much of its heat, though you may need to cook the galette for another minute or two. 

Let the galette cool completely before serving.

The galette can be covered and stored at room temperature for up to 1 day or refrigerated for up to 2 days.