In this simple spaghetti recipe, fennel pollen is used. From googling it, it sounds like MSG :). I'd rather not buy it since it's so expensive, so is there any way to substitute this stuff in the recipe?
You might try ground fennel seed, or even anise, but they will not have quite the same quality. You would certainly have to increase the quantity.
In situations like this, I have to point out: it does not make sense to make a dish where you are forced to substitute for the ingredient which gives the dish its identity. Instead, make something where you can employ the star ingredient.