Set oven to 375ºF. Brush one side of tortillas with butter, then sprinkle with cinnamon sugar. Cut into quarters and place in single layer on a baking sheet. Bake 10-12 minutes. Remove and let cool on the baking sheet. They will continue to crisp as they cool.
Meanwhile, blend the cheese with 1/4 cup powdered sugar until smooth. Add the zest of the orange (about 1 teaspoon).
Mix the strawberries with the liqueur (if using) and brown sugar. Set aside at room temperature.
In a small bowl, whisk 1 tablespoon of the orange juice with 2 tablespoons sugar and the sour cream.
Top each tortilla chip with about a tablespoon of cream cheese, spoonful of strawberries and a drizzle of sour cream sauce. Serve quickly.