Mascarpone

1. Read through the recipe and review any terms and techniques you aren't familiar with. Assemble your equipment, supplies, and ingredients, including a dairy or kitchen thermometer; clean and sterilize your equipment as needed and lay it out on clean kitchen towels.
2. In a nonreactive, heavy 2-quart saucepan with a lid, whisk together the cream and powdered milk. Place over low heat and slowly bring to 180°F, stirring constantly to prevent scorching. It should take about 40 minutes to come to temperature. Turn off the heat.
3. Slowly squeeze the juice from half of the lemon into the cream. Switch to a metal spoon and keep stirring; do not use a whisk, as that will inhibit the curd formation. Watch carefully to see if the cream starts to coagulate. You will not see a clean break between curds and whey. Rather, the cream will coat the spoon and you will start to see some flecks of solids in the cream.
4. Add the juice from the remaining lemon half and stir with the spoon to incorporate. Cover the pan and cool the cream in the refrigerator for 8 hours or overnight.
5. When the cream is firm to the touch, transfer it to a bowl or colander lined with clean, damp butter muslin. Draw the ends together and twist into a ball to squeeze out the excess moisture. This last step will make the mascarpone thick.
6. This cheese is now ready to eat. It has a very short shelf life, so refrigerate what you don't eat immediately and use it within 2 days.