I don't really use a recipe, I just estimate, but basically to make about a cup of pesto:

2 cups of packed basil leaves
2 or 3 cloves of garlic, according to your taste
1/4 cup of pine nuts or walnuts (I personally like walnuts)
1/4 cup olive oil
1/4 cup parmesan cheese, freshly grated is best
Dash of salt and pepper
Some people add a little bit of lemon but I don't

I put the walnuts in the blender first, along with the garlic which I've already put through a garlic press. Then I add some olive oil and pulverize. Then I gradually add the basil leaves, pulverizing a little at a time, and adding more olive oil if necessary. At the end, I blend in the grated cheese. You can adjust these quantities to suit your taste (hard to go wrong). If you want to really do it the right way, it all should be pulverized with a mortar and pestle, if you have them. But it turns out great in the blender. You can add in a little parsley if you like, I think it improves the color. Last year I froze mine in the ice cube tray then transfered to a zip lock bag once the cubes were frozen. This year somebody said you can just put it in a zip lock, flatten it out and freeze, then break off what you need, so that's what I did.