Heat the olive oil in a large pot (preferably a Dutch oven) over medium heat.
Once the olive oil is warm and shimmery, saute onion until golden and translucent.
Add in garlic and saute for a couple of minutes.
Add in sweet Italian chicken sausage and break it into small pieces as you're cooking it. Stir and cooked until it's browned.
Add in sliced mushrooms and cook for 5 minutes until the mushrooms release their juice.
Next, add tomato paste and crushed tomatoes, mix well so everything is incorporated.
Season with salt and oregano.
Add in water, bring to simmer and cook for 10 minutes.
Add in baby spinach and cook for 5 minutes until they start wilting.
Add in gnocchi and cook for three minutes until they start floating.