Combine the flour, sugar, oil, egg and vanilla in a medium bowl. The dough should be a little crumbly.

Spread and pat down about 3/4 of the dough into a greased 9×13 pan, saving the remaining dough for the topping. The dough should be ¼ inch thick once it’s pressed in and the dough is firm.

Place the Biscoff Cookie Butter in a microwave safe bowl and microwave for 15 seconds to help soften the butter.

Spread all the cookie butter over the dough, then sprinkle the remaining dough and crushed Lotus biscuit all over the dough.

Bake at 350 degrees Fahrenheit for 30 minutes.

Once the bars have cooled slightly, cut them into squares.