Begin by bringing a large pot of salted water to a boil. Once boiling, add the casarecce pasta and cook according to the package instructions until al dente. Reserve about ½ cup of the pasta water, then drain the pasta in a colander.
In a large skillet over medium heat, add a splash of olive oil. Once hot, add the sliced baby Bella mushrooms to the skillet. Sauté for about 5-7 minutes until the mushrooms are golden brown and have released their moisture.
Add the minced garlic to the skillet and sauté for another minute until fragrant. Then, add the halved cherry tomatoes to the mix. Cook for an additional 3-4 minutes until the tomatoes start to soften.
Add the baby spinach to the skillet, stirring until wilted. This should take about 1-2 minutes.
Add the drained pasta to the skillet with the sautéed vegetables. Toss everything together, adding a bit of the reserved pasta water to create a light sauce. Season with sea salt, black pepper, and red pepper flakes to taste.
Once everything is well combined, remove from heat. Serve the Mushroom Spinach Pasta warm, garnished with a sprinkle of additional red pepper flakes for an extra kick, if desired.
