I had these delicious puffs at a New Year's Eve party I attended and was instantly hooked. When I got up the next day, I did a quick Google search for "cheese puffs" and the following recipe popped up. The photo looked just like the ones I'd had the night before, and when I made them later that week, sure enough, it was the same (or awfully close). The ones I had were made with Gruyere, but I had cheddar on hand, so that's what I used. Bottom line is that these are easy and will be a hit at any gathering you attend. This recipe is courtesy of www.simplyrecipes.com.
In a medium sized saucepan, add the water, butter, and salt, and bring to a boil over high heat.
Reduce the heat to medium and add the flour all at once. Stir rapidly. The mixture will form a dough ball that will pull away from the sides of the pan. It helps to use a wooden spoon to stir as the dough will be rather thick. Continue to cook for a couple minutes.
Remove the pan from the heat and place dough into the metal bowl of a stand mixer to allow it to cool a little, so that the dough will be warm, but not so warm as to cook the eggs when you add them. Mixing at low speed in a stand mixer helps with this step.
Add the eggs, one at a time, stirring after each addition until the eggs are incorporated into the dough. (If you don't have a stand mixer or hand mixer, use a wooden spoon.) The dough should become creamy, shiny and elastic.
Stir in the grated cheese, thyme, and a few grinds of pepper.
Spoon out small balls (about a heaping tablespoon) of the dough onto a Silpat or parchment lined baking sheet, with at least an inch separating the spoonfuls. Place in oven and cook for 10 minutes at 425°F. Lower heat to 350°F and cook for another 10-15 minutes, until puffed up and lightly golden.
These puffs will be slightly crispy when they first come out of the oven, but will soften a bit as they cool. They can be eaten hot or cold.