You'll find no shortage of yogurt brands on supermarket shelves these days. Still, as far as we're concerned, nothing beats homemade; doing it yourself allows you to make creamy, fresh-tasting yogurt that's exactly as tart as you like. Electric makers are easy to use, but the process is simple even without one. You'll need a bit of yogurt with live active cultures (bacteria that kick off fermentation) to use as your starter and a warm oven to provide the right conditions for bacteria activation. Bring 4 cups milk to a boil in a 2-qt. saucepan; transfer to a 1-qt. heatproof glass bowl or plastic container. Allow to sit until an instant-read thermometer inserted into the milk reads 90°, which could take up to an hour depending on the ambient temperature in your kitchen. Heat oven to 200°. Stir in 1 tbsp. plain full-fat yogurt and cover tightly with plastic wrap or a lid. Wrap in a large, thick dish towel and fasten with rubber bands or string; transfer to oven and immediately turn off the heat. Let the yogurt sit until slightly thickened, 12–24 hours. (The longer the yogurt sits, the more sour it will become.) Remove the towel and chill yogurt 1 hour before serving with fresh berries, if you like. Makes 1 qt.