Roasted, salted dry chickpeas are a snack food.
I would not expect for you to be able to make humus out of them; for one thing, they would have way too much salt, and the texture would be wrong. It might be possible with a lot of experimentation, but you'd need to go through several failed batches before you got one which worked. Personally, I'd just go back to the store.
In Israel I have often seen hummus/falafel/thina served with a hot sauce called skhug, I have mostly seen the green variety (skhug yarok), which is a sauce made of fresh herbs, garlic, chili, lemon juice, garlic, olive oil, and some spices.
Hummus is often just served with thina on the side and with olive oil, but there is a lot of variety ... I have seen sauces based on olive oil and lemon juice, similar to what you describe (although not biter ... but the bitterness could also come from blending the olive oil). But I never saw it being prepared in front of me or it being called a particular name, but it looked a little like a thin vinaigrette.
Using my extremely limited hebrew knowledge and google I found this recipe.
The ingredients translate to:
2 hot chilies
3-4 cloves of garlic
3 tbsp olive oil
juice of half a lemon
salt
additional recomendation:
1 tsp cumin
sugar
Preparation: Put all ingredients into the food processor and turn into the sauce. Taste and adjust spices/oil/lemon juice to taste. And add sugar if too sour to balance the flavor.
You can let sit a little for the flavors to combine ... and strain out remaining bits if desired.
I am not sure if this is the sauce that you had ... but it could be very similar. Anyway ... it sounds tasty.
Best Answer
There are three considerations for deciding whether to skin them or not.
I, for example, like the texture that the skins add to hummus, but I only mash my chickpeas very roughly with a fork and find the ultra smooth variants texturally unpleasant.
Some people use a food processor to make hummus, which allows for quite a smooth product with the skins still, in though not as silky smooth as with them removed, the flavour may be marginally different.
For some people there will be dietary reasons for using peeled chickpeas, for instance Crohn's' Disease sufferers may tolerate hummus without skins better than with.
More traditionally, a silky smooth texture is prized for hummus and that is achieved by using only the meat of the beans.
What most people get wrong about making hummus By Maureen Abood
So essentially, your hummus, your kitchen, your choice.