In a medium mixing bowl, add gluten-free flour, butter, sugar, and salt. Using a pastry cutter or two forks or your hands, blend ingredients together until mixture is crumbly. In a separate bowl, mix together yeast, beaten egg, and milk. Add milk mixture to dry mixture. Continue to mix until blended. The dough will feel slightly sticky.

Place dough on large piece of plastic wrap (at least 11 x 17 inches). Flatten dough into a disc and wrap it in the plastic wrap. Refrigerate for 1 hour or longer.

When dough is ready, preheat oven to 350° F. In a small bowl, mix together sugar and cinnamon for the filling. Melt butter and set aside. Remove dough from refrigerator and open plastic wrap. Leaving dough in center of wrap, take a second similar size piece of plastic wrap and lay it on top of dough disc. Using a rolling pin, roll dough out into a ⅛-inch thick, 11 x 17-inch rectangle.

Brush dough with 3 tablespoons melted butter and then cover evenly with cinnamon sugar mixture and raisins (if using), reserving 2 teaspoons of sugar mixture. From the long ends, roll each side toward the center until both sides meet. Roll assembled Kringle off the plastic wrap and onto an ungreased cookie sheet. Brush dough with the remaining 1 tablespoon butter and sprinkle with the remaining 2 teaspoons sugar mixture.

Bake 20-25 minutes, until slightly firm to touch. Remove from oven and let sit for 10 minutes while making glaze. To make glaze, simply whisk together powdered sugar, butter, milk, water, and vanilla until smooth. Top Kringle with glaze, slice, and serve.