For extra flavor, you can add 1/2 teaspoon garlic powder or smoked paprika to the onion soup mixture before pouring it over the fries. If you like a little heat, sprinkle in a pinch of red pepper flakes or serve with jalapeño slices on the side.
To make these more like fully loaded fries, top the finished dish with crispy cooked bacon bits, sliced green onions, or diced tomatoes right before serving. You can swap the sharp cheddar for a Mexican blend, Colby Jack, or pepper jack cheese for a different twist.
If you prefer a milder onion flavor, use half the packet of dry onion soup mix and taste before adding more next time. For easier cleanup, line the slow cooker with a slow cooker liner, but still keep an eye on the edges so nothing overbrowns.
Food safety tips: Always keep the fries frozen until you’re ready to add them to the slow cooker, and don’t let the finished dish sit at room temperature for more than 2 hours—after serving, either keep it on WARM in the slow cooker or refrigerate leftovers in a shallow container within that time frame. Reheat leftovers thoroughly until steaming hot in the microwave or oven before eating, and discard any leftovers that have been left out too long on a buffet table.
