Slow Cooker Yogurt
Be sure to save a little yogurt as a starter for the next batch. Over time your homemade yogurt will start to lose its potency as starter, so every fourth or fifth batch you may need to use store-bought yogurt as starter.
You can skip the milk powder, but your yogurt won't be as thick. Likewise, you can increase or decrease the amount of milk powder used to achieve thicker or thinner results.
For a super-thick, Greek-style yogurt, simply strain your yogurt after it has set. You can place muslin or a coffee filter in a fine sieve, then add the yogurt and set it over a bowl to catch the liquid. Strain overnight in the fridge.