In a large bowl, mix together the room temperature butter and sugar using a hand-held or stationary mixer until well combined for 2-3 minutes.
Add the spices, salt, and mix to combine.
Add the eggs one at a time and mix after each egg.
Add the flour, baking powder and mix until the flour is incorporated. I like adding a lid at this point so that the flour doesn't get all over the counter.
Add the cream (or milk) and mix again until a smooth batter forms.
Line a 12 muffin tin with cupcake liners.
Scoop a big tablespoon of the batter into each cupcake liner. Add a teaspoon of the cookie butter on top of the batter, then cover with the remaining batter.
Bake for 20 minutes or until a toothpick inserted into the cake part of the cupcake comes out clean.
Let cool for a little bit and dust with icing sugar if using.
These Cookie Butter Stuffed Cupcakes aren't very sweet. In my family we like less sweet desserts but I suspect that many people would find the amount of sweetness not sufficient, so feel free to increase the amount of brown sugar by 1/4-1/2 cup. Or add your favourite buttercream.If you have pre-mixed speculaas spices, you could use 1+1/4 to 1+1/2 teaspoons of your own speculaas spices instead of the spices in this recipe.