Easy Cranberry Orange Muffins

Preheat the oven to 400 degrees F (200 degrees C). Grease 5 cups of a muffin tin or line with paper liners.

Whisk flour, sugar, baking powder, and salt together in a bowl until evenly blended. Pour vegetable oil in a measuring cup. Add egg and enough milk to fill the cup; stir to combine. Pour oil mixture into flour mixture and mix to combine. Stir in orange juice and orange zest. Fold in cranberries until batter is just combined. Spoon batter into the prepared muffin cups, filling each about half way.

Bake in preheated oven until tops spring back when lightly pressed, 15 to 20 minutes. Cool in the tin for 5 minutes. Transfer to a wire rack to cool completely.