Mushroom Melt with Dill Aioli

Ingredients (12)

• + 1 garlic clove, chopped add to pantry
• ✓ 1 teaspoon lemon juice
• + 1 egg yolk add to pantry
• ✓ ¼ cup olive oil
• + 1 teaspoon dried dill weed add to pantry
• + ½ teaspoon salt add to pantry
• + cayenne pepper, to taste add to pantry
• ✓ 2 tablespoons butter
• + 2 slices whole wheat bread add to pantry
• + 4 thick slices Cheddar cheese add to pantry
• + 2 large mushrooms, chopped add to pantry
• + 1 cup fresh baby spinach add to pantry