Combine spinach, mushrooms, and almonds in a large serving bowl; set aside.
Heat oil in a small frying pan over medium heat. When it shimmers, add garlic and shallot and season well with salt and freshly ground black pepper. Cook until garlic is browned, about 2 minutes, then add vinegar and stir to incorporate. Remove from heat and stir in honey until dissolved.
Pour vinaigrette over salad and toss to coat. Serve immediately.