In a medium sauce pan bring the milk and cream to a gentle boil together with the sea salt. Squeeze in the lemon juice, stir and cook for a couple of minutes until it curdles. Remove from heat and let it sit for a few minutes.
Strain the mixture into a bowl through a mesh strainer lined with the cheesecloth. Transfer the homemade ricotta cheese to a bowl and discard the cheese cloth. Serve fresh or refrigerate up to 5 days.