1. Saturate a large piece of doubled cheesecloth or a fine-textured cotton kitchen towel with cold water. Wring it out thoroughly and place it in a colander or fine-mesh sieve set over a large bowl.

2. Bring the milk and salt to a near boil in a large heavy-bottomed pot over high heat, whisking often so it doesn't scorch (once steam starts to rise off the top, watch the milk closely--it can boil over quickly).

3. Remove the pot from the burner and whisk in the lemon juice. Return the pot to medium-low heat and cook, stirring occasionally, until the mixture looks curdled, 1 to 2 minutes.

4. Pour the milk into the cheesecloth-lined colander and drain until the cheese comes together and looks fine textured, about 1 minute (if using a kitchen towel, it will take 2 to 3 minutes; lift an edge of the towel and gently shake it a few times while the ricotta drains).

5. Gather the corners of the cheesecloth, lift the ricotta out of the colander and turn it out into a container or glass bowl. Cover and refrigerate for up to 3 days. (That said, it really tastes best immediately after or within a few hours of making.)