Trim all four edges of the dough to create clean, straight sides. Save scraps for other projects. Cut the dough horizontally into strips that are 1 to 1.5 inches wide. Cut the entire rectangle in half vertically down the middle. Place strips on a parchment-lined baking sheet, spacing them about 2 inches apart.

In a small bowl, combine sugar, cinnamon, cardamom, nutmeg, and sea salt. Mix thoroughly until evenly distributed. In a separate small bowl, combine melted butter and vanilla extract if using.

Brush each dough strip generously with the melted butter mixture, making sure to coat all surfaces. Generously sprinkle the cinnamon sugar over each strip while the butter is still wet. Press gently to help it adhere.

Cover the baking sheet loosely with plastic wrap or a damp tea towel. For cold proof, refrigerate for 8 to 12 hours or overnight. For room temperature proof, leave at 70 to 75°F for 4 to 6 hours. Dippers are ready when they’ve increased in size by 50 to 75% and the layers begin to separate visibly.

Cut cold cream cheese into small cubes and beat in a mixing bowl until smooth, about 1 minute. Add slightly softened butter and beat until completely combined with no lumps, about 2 minutes. In a separate bowl, sift together powdered sugar and cornstarch. Add sugar mixture to cream cheese mixture in two additions, mixing on low speed. Add vanilla and salt. Beat on medium speed until light and fluffy, 2 to 3 minutes. If too thick, add heavy cream 1/4 teaspoon at a time until desired consistency is reached.

For drizzling, transfer frosting to a ziplock bag, snip a small corner, and drizzle over cooled dippers. Let set for 2 hours before serving. For dipping, serve frosting in a bowl alongside warm or cooled dippers for dunking.