Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x13-inch baking pan.
Mix flour, brown sugar, 1 cup margarine, eggs, 2 teaspoons vanilla extract, and 1 teaspoon baking soda together in a bowl until combined. Stir in oats. Press 2/3 the mixture into the bottom of the prepared pan.
Melt butterscotch, chocolate chips, and 2 tablespoons margarine in a saucepan over medium heat. Stir in condensed milk and 2 teaspoons vanilla extract until smooth. Pour into the baking pan; crumble remaining oat mixture on top.
Bake in the preheated oven until set, about 25 minutes. Cool for at least 10 minutes. Cut into squares.
