Preheat oven to 400°F degrees. Place bonMat on perforated baking sheet.
Add water, brown sugar, salt, vanilla and 4 Tbsp butter to a saucepan. Cook over medium heat until butter is melted. Add flour to butter mixture and stir with heat resistant spatula until the mixture turns into a thick paste. Cook for 1 minute until dough forms into a smooth ball. Set aside dough.
Whisk egg in mixing bowl. Add dough to egg and mix until fully incorporated. Set up pastry bag with largest star tip in pastry bag stand. Fill pastry bag with dough. Create 3 inch long churros on the bonMat. Using your silicone pastry brush, brush each churro with melted butter. Bake for 25 minutes, until churros are crisp and browned.
While they are baking, combine sugar and cinnamon in mixing bowl. Add warm churros to cinnamon sugar mixture and toss with Versatile Tongs to coat. Enjoy!