Step 1: Ingredients and Cost
Butter (to lightly coat)
Parmesan Cheese (to lightly coat)
Basil (fresh and minced or dried)
Calculating cost doesn't work very well as ratios depend on the amount being served. I think we can agree the cost is VERY low ;)
Step 2: Cook and Serve
Boiling water for pastas actually has more steps than just placing a pot of water over heat ;)
1. Place a covered pot over heat
2. When bubbles start rising (creating a convection current) salt the water. You know you added it at the right time because the water will turn cloudy for a few seconds - recover
3. Once the water is boiling, add 1-2 tablespoons of good olive oil - do not recover
Cook your pasta for the desired amount of time. I cooked this pasta (spaghetti Rigati) about 6 minutes. The recommendation is 7-9 minutes. I find that too long and my pasta comes out too mushy. I was raised on extra al dente. Al dente means to the bite (or teeth) in Italian. One method of testing doneness is to sample your pot and make sure the pasta retains a little bite.
Pasta type is also important. Rigati has a mostly square cross section which brings in some texture and allows things to stick to it easily. If you were serving a sauce with small chunks of something, you'd want something bigger like Rotini or gemelli. This also goes for thick cream sauces (which is why you may have had mac and cheese using wagon wheels). Tubular pastas are great for heavy sauces - they are sturdy enough and have a nice cavity to hold the goods. I can explain more about pasta selection later.
Strain your pasta - do not rinse
Place the pot back on the burner (now turned off) and throw in a few pats of butter. Use your best judgment - we want to lightly coat everything. Melt butter.
Put the pasta back in the pot and mix well -- now sprinkle in some Parmesan cheese and basil to, again, lightly coat. Roasted garlic and/or roasted peppers (rough chop) also adds great flavor (and color).