Grab 1 cup milk - make it room temperature if you're planning to bake something with it. Choose any milk you like, but if you're going for the non dairy products route, be ready for a little twist in flavor and texture. Now, the magic happens! Take a tablespoon of lemon juice or tablespoon vinegar and pour it into the fresh milk. Give it a good stir and then leave it be for a little bit of time, around 5-10 minutes. Watch the transformation unfold as the milk curdles and thickens, giving you that tangy goodness we all love.