This Biscoff Muffins recipe results in moist, fluffy muffins. Made with speculoos cookie butter and topped with a quick biscoff streusel; the crushed biscoff cookies and the drizzling with more melted biscoff spread is optional, but definitely recommended!Biscoff Muffins are perfect for biscoff lovers! If you’ve been reading my blog through out the years, you’ll know how much I love anything biscoff. I could eat it by the spoonful.