Heat 1 tablespoon of the olive oil in a medium nonstick skillet over medium-high heat. Add the cauliflower gnocchi. Cook 3-4 minutes per side, until the gnocchi is golden brown & crispy. Transfer to a plate & set aside.
Add 1 Tbsp olive oil to the skillet. Add the onion & season generously with S&P. Cook 3-4 minutes, until softened. Add the Italian sausage to the skillet. Brown the sausage 5-7, using a wooden spoon to break it into bite-sized crumbles as it cooks – if needed, add an extra tablespoon of olive oil to help it brown up nicely.
Stir the garlic, Italian seasoning, & red pepper flakes (if using) into the sausage & onion mixture. Cook 30 seconds, until fragrant. Stir in the kale & cook 2-3 minutes longer, until the kale is vibrant green & softened slightly. Stir in the chicken stock, heavy cream, & grated parmesan. Bring the mixture to a simmer.
Add the toasted cauliflower gnocchi back into the skillet. Stir to combine well. Simmer 1-2 minutes, then remove from the heat. Finish the cauliflower gnocchi skillet with a good squeeze of lemon juice. Taste & adjust seasonings as needed.