Pour the gallon of milk into a large stainless steel or other non-reactive stockpot. Sprinkle the citric acid over the top and stir in gently. Heat milk to 88°F. Don’t panic when the milk starts to curdle. That’s the idea!
While pot is still over heat, stir the diluted rennet in gently making sure to stir all of the milk (don’t just top-stir!) Once the milk reaches between 100-105ºF, kill the heat. WALK AWAY FROM THE PAN for about 5 minutes. I mean it. Do not touch that pan.
When you come back, the curds (the white part) should’ve pulled away from the sides of the pot and you should see lots of whey (yellowish clear liquid) on top and around the sides. If the whey is still milky looking, wait a couple more minutes. This is not a bad thing… All milk is different.
Now comes the fun part. Scoop the curds out of the pot with a slotted spoon and put them into a microwave safe 2 quart or larger sized bowl. Gently press the curd together against the side of the bowl with your hand. You’ll probably have lots of whey coming off the curd. Drain the whey off back into the stockpot and DON’T THROW IT AWHEY, er, AWAY, that is!***
***Whey is incredibly healthy for you. Use it in place of milk when baking bread to really improve both the health quotient and the texture of your loaves. I’ve heard it said that chilled whey, mixed with fresh squeezed lemon juice and sugar makes a refreshing drink. Um, sure. I’m not quite there yet, but I do use it in my bread when it’s available and it is wonderful!
Put the bowl of curds into the microwave and nuke on high for 1 minute. Use your hands to hold the cheese in the bowl, and drain the extra whey back into the stockpot. Make like you’re kneading delicate bread dough and use your impeccably clean hands to gently fold the cheese back on itself over and over. Again, drain any excess whey back into the pot.
Return the bowl to the microwave and zap it for 35 seconds more. Knead the curds and drain the whey again.
Return once more to the microwave and give it 25 more seconds. Drain off the whey, add salt, if using, and knead until the curds are shiny and stretchy like taffy. You can continue to microwave it in small 10-20 second bursts if the curds cool down to the point where they’re snapping or breaking rather than stretching. At this point you can either stretch it into a smooth ball and eat it warm, drop the ball in ice water to cool the curd quickly for storage OR…
Pull off little pieces of mozzarella, between walnut size and golf ball size and stretch and roll it to form little balls. Drop little balls into an ice water bath and repeat with the remaining curd. While the bocconcini (’cause that’s what they are now) cool, move on to prepare the pesto.
To Make the Pesto:
To toast almonds, add them to a heavy-bottomed skillet over medium heat. Keep agitating them until they smell toasty and nutty and they’re taking on a delicate brown color.
Remove the almonds from the heat immediately and throw into the food processor with the garlic, basil, salt and pepper. Pulse until the basil leaves are torn very small and the nuts and garlic have been minced. With food processor running, pour the olive oil in a steady stream through the feed tube.
When olive oil is fully added, turn off food processor and add the grated cheese and lemon zest, if using. Pulse four or so more times to mix in the cheese and zest. Now you can use it for pasta, or as a filling in bread rolls OR…