Cook confidently with a few simple tricks to quickly and easily thicken mashed potatoes. Each method takes only minutes and uses a single ingredient or basic kitchen technique.
What Makes These Methods So Effective
- Fast and practical for when you’re short on time — each method takes only minutes to thicken mashed potatoes to the texture you want.
- Flexible options that work with common pantry items or simple kitchen tools, so anyone can rescue runny mashed potatoes.
- All techniques focus on texture, not flavor — when used correctly, they won’t compromise the taste of your mashed potatoes.
The 5 Methods to Thicken Mashed Potatoes
Method 1 – Use a Thickening Agent
Starch-based thickeners like cornstarch or flour are very effective. Cornstarch is preferred because it thickens without altering flavor. Add cornstarch one tablespoon at a time, stirring after each addition, until the potatoes reach the desired consistency. If you use flour, mix it with a little cold water first to avoid lumps and add sparingly to prevent a pasty texture.
Method 2 – Heat in a Pot
Transfer runny mashed potatoes to a medium pot and warm over medium heat, uncovered. Stir gently every minute to prevent sticking. Leaving the pot uncovered lets excess moisture evaporate, naturally thickening the potatoes. Be careful not to over-stir or mash vigorously, as this can make them gummy.
Method 3 – Add Dehydrated Potato Flakes
Instant mashed potato flakes are an excellent quick thickener and are designed to blend smoothly into mashed potatoes. Sprinkle in one tablespoon at a time and mix until the texture is right. This method thickens in seconds and maintains a creamy potato flavor.
Method 4 – Bake in a Shallow Dish
Spread the mashed potatoes in a shallow 9×13 baking dish and bake uncovered at 350°F (175°C) for about 10 minutes, or until the excess moisture has evaporated and the potatoes have thickened. This gentle drying technique concentrates the texture without changing the flavor.
Method 5 – Add More Cooked Potatoes
Cook additional potatoes the same way you prepared the originals, then mash them dry (without adding extra milk or butter) and fold them into the runny batch. Add cooked potatoes a little at a time until you reach the desired thickness. This is a great option when you want to preserve the potato’s natural texture and flavor.
Chef’s Tips for Perfect Mashed Potatoes
- Avoid overworking the potatoes. Excessive mashing or mixing can make potatoes gluey. Mash gently and stop when they’re smooth and combined.
- Mash before adding liquids. Boiled potatoes can hold a surprising amount of water. Give them a quick dry mash to evaluate consistency before adding milk, cream, or butter.
- Don’t throw them away. If potatoes are beyond saving as a side dish, turn them into a comforting soup, shepherd’s pie filling, or add them to a casserole.
Recipe Details: How to Thicken Mashed Potatoes (5 Ways)
How to Thicken Mashed Potatoes (5 Ways)
Ingredients
- 4 cups runny mashed potatoes
- Cornstarch (optional)
- Dehydrated potato flakes (optional)
- Additional potatoes, peeled, boiled, and mashed (optional)
Equipment
- Medium pot
- 9×13 baking dish
Instructions
Method 1 – Use a Thickening Agent
- Add one tablespoon of cornstarch at a time, stirring after each addition until the potatoes reach the desired thickness.
Method 2 – Heat in a Pot
- Warm the mashed potatoes in a pot over medium heat, uncovered, stirring gently every minute until moisture evaporates and the texture firms up.
Method 3 – Add Dehydrated Potatoes
- Stir in instant potato flakes one tablespoon at a time until the consistency is right.
Method 4 – Bake in a Shallow Dish
- Spread potatoes in a shallow dish and bake at 350°F for about 10 minutes, uncovered, until excess moisture has evaporated.
Method 5 – Cook Additional Potatoes
- Cook and mash extra potatoes without additional liquid, then fold them into the runny potatoes a little at a time until thickened.
Notes
Recipe yields approximately 8 servings; actual servings depend on portion sizes. Nutritional values are general estimates and will vary by ingredient choices and optional additions.
To calculate the weight of a serving, weigh the finished dish and divide by the number of servings desired.
Nutrition Information (per serving)
Serving: 1 | Calories: 106 kcal | Protein: 3 g | Fat: 1 g | Total Carbs: 24 g | Fiber: 2 g | Sugar: 1 g
Author: Cheryl Malik
More Kitchen Tips
- When in doubt, warm and dry the potatoes slowly — evaporation is often the simplest fix.
- Keep additional thickeners on hand like cornstarch or instant potato flakes for quick adjustments.
- Remember texture first: once consistency is right, you can always reintroduce butter, cream, or seasonings to taste.