Question: I recently ate at a Mexican restaurant with a delicious sauce. They were willing to sell it to me if I put in a special order, but they insisted it was so easy to make that I should just make it myself instead. I know the ingredients are jalapenos, habaneros, onions, and garlic. There is no water or anything else, just those four ingredients. The end result is a yellowish green sauce with a smooth, almost paste consistency.

I think I can figure out cooking the ingredients and blending them together, but how do I even take a guess at the ratios? None of the flavors were overpowering (it didn't taste mostly like onions or jalapenos or garlic), so there's not an obvious base, but I doubt they're anywhere close to equal proportions either. I don't need the results to be an exact match, but I'd like it to at least resemble what I had in the restaurant. 

What's the best approach to this?

Answer: 
If it is instant oatmeal, just add boiling water (ratio water to oats 2/1) and let it sit for 5 minutes. If it not instant, same ratio of water to oats, boil for 5 minutes while stirring, remove from heat, cover and let sit for 5 minutes.
I googled "how to cook oatmeal" and found several similiar ways.
Common "rolled" oats are flattened into fat disc-shaped units; "quick" oats are rolled and then further sliced thin to cook faster. "Steel cut" oats are just cut into small hard pieces like short rice grains.

For quick oats, add about 2:1 water to oats, and cook until done to desired softness, which should be a few minutes. For rolled oats, cook longer and maybe add a little more water to account to evaporation. For steel cut oats, go up to 3:1 or even 4:1 on the water, and cook for 30 minutes or more (or let soak overnight and cook for 10 minutes). They'll need some salt, but not much.