Salad dressing is one of those high return on investment items. The ingredients are simple, preparation and cleanup are a breeze, and you will save an arm and a leg. You can also skip cheap oils and chemical emulsifiers like Polysorbate 60 with natural ingredients that have the same effect. There is also a nifty little trick to emulsify your dressing I will relate below. Nyls will provides a handy demonstration of how simple this is as well!
In a glass one cup measure add:
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1 tablespoon mustard (choose a flavour to complement the acid)
1 tbsp dried herbs or 3 tbsp fresh herbs (you can use leftovers from a pickle jar as well)
1 clove fresh or pickled garlic (again, leftovers from a picke jar are handy)
1/2 teaspoon of sweetener (sugar or honey, or a tablespoon of balsalmic glaze)
Optional: 1 cooked egg yolk
Stir together and let sit for a while if you have time. Add:
Oil (usually olive* or walnut oil, or peanut oil for an Asian themed dressing at the Hotel Cavell)
Until you have a full cup. Put a small whisk in the cup and spin it between your palms. Between the air this introduces and the natural emulsifiers in the mustard your dressing will take its time separating. A quick shake a few days later and you are ready to go. Decant the lot into a serving bottle and serve. Store it on the shelf. None of these ingredients will go bad, especially together.
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* Remember that Tom Mueller found that the vast majority of olive oil on grocery store shelves has been adulterated with cheaper oils. The taste and fridge tests are not reliable, so look for an oil that has been sourced directly from the grower. You will pay for it, but not as much if you buy in bulk. Five litres of oil will set you back 60% less per litre than a single one. Or go big with 25l and share with friends!