Prepare a batch of same-day focaccia dough following the recipe instructions up until tipping the dough into the tray
While the dough is proofing, make the cinnamon sugar butter filling by mixing browned butter with brown sugar, cinnamon and vanilla extract
Set the filling aside
Line parchment on the tray with 2 tablespoons melted salted butter instead of olive oil
Transfer the dough to the 9x13 inch tray and gently stretch to edges
Mix ⅓ of the diced apples with half of the cinnamon filling and spread over the dough
Fold up the dough as shown in the video
Flip the dough over and cover to finish proofing at room temperature for 1-1.5 hours
Preheat oven to 215C/420F with rack in lowest position
Warm up the cinnamon sugar butter to drizzling consistency and mix with remaining ⅔ diced apples
Spread the apple mixture over the top of dough evenly and dimple in
Bake for 23-25 minutes
While baking, whisk together powdered sugar, milk, vanilla extract and cinnamon for the glaze
Drizzle glaze over the focaccia once out of oven and brush on top, sides and bottom
Transfer to cooling rack for glaze to harden for about 15 minutes
