Why does my curry taste so bland? I'm trying to make a curry, and failing. I'm a decent amateur home-cook, but now that I'm exploring outside of my usual cuisines, I'm at a loss how to improve my preparation of this recipe. Either that, or the recipe might just be of questionable quality... which would also be good to know.

Following this recipe (automatic translation here), I end up with something that looks and smells very much like a curry, but it tastes very flat/bland, while still hot/spicy.

I'm not used to talking about flavour so forgive me for this poor attempt at describing the taste (any hints on how to learn that skill?). It's spicy, but only as an after-taste, mostly in the back of the throat. Most curries I've eaten in Indian restaurants had a real strong flavour right at the first impact, which mine is lacking. Adding questionable amounts of salt after serving helped a little bit, but felt like a cheap trick to mask the issue.
The recipe is easy on spices with (perceived) spiciness: No peppers, just the usual amount of ginger and only 2 cloves. On top of that, close to half a liter of coconut milk gets added, which will sweeten the curry, and dampen the (again: perceived) spiciness.

The main veggies are cauliflower, far from the most exciting taste in the world, and peas, which tend to have a sweet taste. 

Also, the amount of veggies (close to a kilo) compared to the amount of the spices seem a tad on the small side. 

Personal observation: I'd have to make it myself to see what (if anything) is missing, but as Chris mentions, some cumin (usually an equal or half part compared to the coriander) might help, as would nutmeg and/or mace, all of which (IMHO) go well with cauliflower. 

I've found that good Indian recipes are hard to find on the internet (or I'm not very good at searching). They tend to be of the Ginger-Garlic-Coriander-Cumin-Cardamom-Blended-With-Tomato-Puree variety, which although definitely tasty, all merge in to the same taste. Maunika Gowardhan has nice authentic recipes, and the slightly dodgy looking India Curry too, together with lots of spice mixes and background information.