Make lemon curd more sour/tart after it’s cooked

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.

Use one teaspoon of dried zest for one tablespoon of fresh zest, which is about what you get from a lemon.

Most foods dry to about a third their original size, so I would use one third of the amount called for. Lemons vary a great deal in size, but the recipe probably means one tablespoon of fresh zest, which is normal for "medium" sized lemons.

Something to watch out for is that most cheap "dried lemon peel" products are actually made from the zest and a bit of the pith, which will both give you a bitter flavor and short you some of the lemon flavor you expect. Look closely at the zest you buy, if you can see that the individual pieces have two distinct layers, or a pale yellow or white color, steer clear of that brand. This is probably a "get what you pay for" situation, so spring for the higher end lemon zest.

I have also had great luck drying my own lemon zest. Unless your kitchen is humid, it will probably dry in a day or two just sitting on a plate on the counter.