Preheat the oven to 350 degrees F. Line a baking sheet with parchment paper or a silicone mat.
In a medium bowl, whisk together the oats, flour, baking soda, cinnamon, and salt. Set aside.
In the bowl of a stand mixer, add the butter, Biscoff spread, sugar, and brown sugar and beat on medium speed until smooth and creamy. Add the egg and vanilla extra and beat until smooth.
Reduce the mixer speed to low and slowly add the dry ingredients, beating only until blended. Chill the dough 30 minutes in the refrigerator.
Form the cookie dough into rounded tablespoons and place them 2 inches apart on the baking sheet.. Bake for 8 to 10 minutes or until cookies are golden and just firm around the edges. Let the cookies cool on the baking sheet for 5 minutes and then remove with a spatula onto a cooling rack.