Prepare the Spinach: Thaw the frozen spinach in the microwave or by leaving it at room temperature. Once thawed, drain all excess liquid by pressing the spinach in a colander or using paper towels to squeeze out the moisture.
Combine the Ingredients: In a large mixing bowl, add the thawed and drained spinach, Knorr Vegetable Soup Mix, sour cream, and mayonnaise. Stir everything together until well combined and the mixture is smooth.
Refrigerate: Cover the mixing bowl with plastic wrap or a lid and refrigerate the dip for at least 2 hours. The flavors will meld together and improve after resting.
Serve: After the resting period, stir the dip again and serve it with crackers, vegetable sticks (carrots, celery, cucumber), or sliced bread for dipping.
