In a large salad bowl, combine the thinly sliced mushrooms, celery, and baby spinach.
In a separate small bowl, whisk together the Meyer lemon zest, Meyer lemon juice, extra virgin olive oil, sea salt, and black pepper to create the dressing.
Pour the dressing over the vegetables in the large bowl.
Add the freshly grated Pecorino Romano or Asiago and toss everything together until well combined.
Serve immediately.
Let the salad sit for 5-10 minutes after tossing. This allows the acidic lemon juice to slightly soften the mushrooms and celery, deepening the flavors.