Preheat oven to 350F. Line a 9x13 baking pan with tin foil and lightly grease. Set aside.
In a large bowl, combine oats, flour, baking soda, and salt. In a separate bowl, beat sugar and sugar until creamy. Beat in yogurt, eggs, and vanilla until smooth. Add flour mixture to liquid, gently stirring until a dough forms. Stir in chocolate chips.
Press dough evenly into prepared pan. Bake bars at 350F 25-30 minutes or until bars begin to turn golden around the edges. Cool bars completely in pan on a wire cooling rack. Slice bars into squares and serve.
Notes
Store bars in an airtight container at room temperature up to 4 days.