When it comes to measurements (except in baking), I always find this part tricky to convey because I truly believe you have total freedom over the look, flavor, texture, and serving size of your dish. Whether you want to make a small portion just for you or a huge pot of pasta for a family of 5, only you can gauge how much of a particular ingredient you want to add. You can't always subtract though, so be careful. It's always better to under-season for obvious reasons.
The way I see it, I can tell you to add 1/2 cup of shrimp, but if you're a SUPER shrimp lover, like my girlfriend, you might want to go full cup here. Ain't nothin' wrong with that! So, here's simply what you need to make that delicious masterpiece you see below ;)
whole wheat pasta
cooked & peeled shrimp
pesto (I used trader joe's basil pesto)
fresh or dried basil
fresh or dried oregano
salt & pepper, of course
1. Boil your pasta.
2. In a saucepan, heat up olive oil and some butter. Add your onions and garlic until translucent. Add shrimp and stir until heated through. Add tomato paste and a little water to dissolve paste and create some sauce. Stir.
3. Add all your seasonings and stir. Add your pesto and let it dissolve in sauce. If it begins to dry out, just add more water (pasta water would be great or even some broth).
4. Now drain your pasta and add it to the shrimp & pesto sauce. Mix.
5. Lastly, add your fresh spinach and cover for a bit until they wilt. Give everything a good mix to make sure all ingredients are fully incorporated.
At this point, you can add anything based on what you think it's missing. Taste your food, people! I swear it's a thing. Need more garlic powder? Add it! More butter? Add it! Need a little heat? Grab the cayenne pepper.
If you have the time, play around. Cooking is experimental and fun! Don't let anyone tell you different. Unless their name is Gordon Ramsay or something. Then, I guess maybe listen or whatever lol ;)