Combine the tomatoes and their juices with the water in a small saucepan and bring to a simmer. Turn heat to low to keep the mixture warm until needed.

In a large pot or sauté pan, combine the sausage and chopped onion and add salt & pepper to taste. Cook over medium heat, breaking the sausage up with a wooden spoon until meat is brown and onions have softened. Add the rice and stir to coat the rice and combine. Cook for 1-2 minutes and then add wine. Stir until wine is absorbed (1-2 minutes).

Add two cups of the tomato mixture to the rice and stir. Turn the heat down to a simmer (medium-low heat) and cook until liquid is absorbed, stirring occasionally. Add another cup and cook, stirring occasionally, until the liquid is absorbed. Continue, one cup of liquid at a time until all of the tomato liquid has been added and absorbed. Rice will be tender and creamy. Add the chopped spinach and stir in until combined. Cook for another 1-2 minutes until spinach is wilted and combined.

Remove risotto from heat and add the butter and cheese. Stir until thoroughly mixed. Serve immediately.