Heat a skillet over medium high heat and add the olive oil. Add the minced garlic and stir about 10 seconds. Add the spinach, reduce heat and cover for about one minute. Stir and cover for another minute or until the spinach is wilted. Cool. Puree the spinach, garlic and scallions in a food processor. Transfer to a bowl and add the sour cream, yogurt, lemon juice, salt and pepper. Mix well. Chill thoroughly.