Pour 8 cups whole milk into a large saucepan or Dutch oven. Heat over medium-high heat, stirring often, until the milk reaches 170°F on an instant-read or candy thermometer.
Stir in ½ cup white vinegar. With the heat still on, stir for 2 minutes. You will see the mixture becoming curdled at this point. After two minutes, turn off the heat and let the mixture sit for 20-30 minutes.
Line a large mesh strainer with cheesecloth (see note). Set the strainer over a bowl. Carefully pour the cheese mixture into the strainer, being careful not to pour too much at a time so that the cheesecloth overflows. Once you've poured all of the mixture in, stir in 1 teaspoon kosher salt, then let the curds sit to drain for 30 minutes.
After 30 minutes, taste the curds in the strainer (at this point, they will still be quite soft). Add more salt if needed, little bits at a time, stirring the curds well between each addition.
Gather the edges of cheesecloth together to form a bundle. Holding the cheesecloth over the bowl (or sink), squeeze the bundle tightly until it stops dripping.
Place the cheesecloth bundle on a clean plate or cutting board, and remove all of the curds from the cheesecloth. Form the curds into a mass, either freehand or by pressing it into an airtight container (pro-tip, place one or two strips of parchment in the container under the cheese so that you can easily lift it out of the container when you're ready to use it). While you can go ahead and eat the cheese now, it's best to refrigerate it for a day to let it firm up.
Serve crumbled anywhere you would use queso fresco - on tacos (try it on zucchini tacos), chilaquiles, salads, eggs, soups, nachos, etc. Store any extra in an airtight container in the fridge for up to 5 days.
Notes
The cheesecloth I have right now (from the dollar store) has a very loose weave. I use 4 layers. If your cheesecloth has a tighter weave (like the one I've linked), you could probably use only 1 or 2 layers.