Heat the olive oil in a large skillet over medium-high heat until shimmering.
Add the chopped shallot and cook, stirring occasionally, until softened about 3 minutes.
Add the spinach and cook, stirring, until wilted; then stir in the minced garlic and cook 1 minute more.
Add the drained cannellini beans and 1 cup vegetable broth to the skillet; season with kosher salt, black pepper, and crushed red pepper flakes.
Bring the mixture to a simmer, then reduce heat and let simmer gently for about 10 minutes, stirring occasionally; break up a few beans with a wooden spoon if you prefer a creamier texture.
Stir in the Parmesan cheese (or nutritional yeast) and 1 to 2 tablespoons lemon juice; add a splash more vegetable broth if the mixture is too thick.
Adjust seasoning to taste and serve warm with crusty bread.
