Spanish Filled Churros

Name: Spanish Filled Churros
Cuisine: European, Mediterranean, Spanish
Ingredients: For the Churro Dough; 1 cup water; 2 tbsp unsalted butter; 1 tbsp granulated sugar; 1/4 tsp salt; 1 cup all-purpose flour; 1 large egg; 1/2 tsp vanilla extract; Oil, for frying; 1/2 cup dulce de leche or thick chocolate ganache; 1/2 cup granulated sugar; 1 tsp ground cinnamon