This recipe is for making ricotta from scratch; if you want to use store-bought ricotta, make sure you buy whole milk ricotta for the best consistency.
Heat milk in a medium saucepan, over medium heat.
Add the salt; sir occasionally with a wooden spoon until the milk reaches 185°F.
The milk will begin to steam with small bubbles close to the edges; about 20 minutes.
Reduce to a simmer and add the lemon juice.
Stir for two minutes until the curds begin to separate from the whey.
Remove from the heat and allow to sit for 20 minutes.
Ladle the ricotta into a cheesecloth-lined colander.
Drain and let sit for 10 to 15 minutes.
Add ricotta to a food processor with olive oil, salt and pepper.
Blend until fluffy and smooth; set aside.
Brush both sides of the sourdough with olive oil and toast in a skillet, over medium heat, until crisp.
Top the sourdough with the whipped ricotta, thyme, honey, salt, pepper and additional lemon juice to taste.