We can buy it ready mixed in the shops, even at a regular supermarket. I looked for a receipy for the mix but do not find a precise one. I guess it is like currie-mixes; endless variations with the different herbs. Some books make a difference between the mix for cookies and typical speculaas, which has a little ginger in the mix.
Cinnamon, Chinese anise, cloves, pimento (Jamaican pepper), orangepeel and lemonpeel, cardemon, ginger, mace and nutmag
I never tried making it myself yet since it's so easy to come by. I used it in crusts for fruitpies because I like the combination of sweet fruits and species. If I come across something else I will let you know. Anyway, it's perfect to make a mix to your own taste. I would skip the peel (better fresh) and use more mace/less nutmag...