Spray a 9x5-inch loaf pan with baking spray with flour. Line pan with parchment paper, letting excess extend over long sides of pan.

In a small bowl, stir butter until smooth and creamy. Add mustard and thyme, stirring until well combined.

On a lightly floured surface, roll Buttery Pull-Apart Dough into a 16x12-inch rectangle (about ¼ inch thick), with one long side closest to you. Spread mustard mixture in a thin layer all over dough. Top with sliced ham, tearing as needed to cover surface fully. Cut dough into 16 rectangles (about 4x3 inches each). Sprinkle with 7 ounces (198 grams) cheese.

Stand prepared pan vertically on one short side. Starting at bottom, carefully layer dough pieces, filling side up, one on top of the other. For final piece of dough, place in pan filling side down. Turn pan upright onto its bottom. Cover and let rise in a warm, draft-free place (75°F/24°C) until doubled in size, 30 to 45 minutes.

Preheat oven to 350°F (180°C).

Bake until golden brown and an instant-read thermometer inserted in center registers 190°F (88°C), about 1 hour and 20 minutes, loosely covering with foil after 45 minutes of baking to prevent excess browning. Sprinkle with remaining 1 ounce (28 grams) cheese. Let cool in pan for 10 minutes. Using excess parchment as handles, remove from pan, and let cool on a wire rack for 10 minutes. Garnish with thyme, if desired. Best served warm. Refrigerate in an airtight container for up to 3 days.