This Purple Sweet Potato Paste is sweet, creamy and versatile—a beautiful filling for mochi, mooncakes, steamed buns and more. Made from purple sweet potatoes (often called Japanese or Okinawan sweet potatoes), this paste highlights their vibrant color and naturally sweet flavor while remaining a wholesome option for desserts and snacks. It’s easy to make, stores well, and you can adjust the texture to suit fillings or spreads.
Ingredients Used to Make Purple Sweet Potato Filling
Simple ingredients, easy techniques. Purple sweet potatoes have a denser, drier flesh than orange sweet potatoes; a bit of added liquid and fat helps create a smooth, spreadable paste ideal for fillings.
- Purple sweet potatoes (mashed) – Use Asian purple sweet potatoes (Japanese or Okinawan). When baked or microwaved they develop a dense, almost potato-like texture that makes a rich, colorful paste. To cook quickly, wrap potatoes for microwave use or place in a microwave-safe container and cook until tender.
- Water – Added a tablespoon at a time to reach the desired consistency. Purple sweet potatoes are often drier, so water keeps the paste creamy rather than crumbly.
- Liquid sweetener (honey, maple or agave) – A small amount brightens flavor and balances earthiness. Adjust to taste.
- Coconut oil or neutral fat (optional) – Adds shine and improves mouthfeel. Use refined coconut oil, plant-based butter, or regular butter if preferred.
Step by Step Guide
This step-by-step method produces a smooth paste suitable for shaping into balls for mochi and mooncakes or spreading into steamed buns and breads.
Step 1
Wash the sweet potatoes well. Place them in a microwave-safe bowl or container if you’re using the microwave for a quick method, or roast/bake them until tender if preferred.
Step 2
Cover the container (leave a small vent if microwaving) so steam can escape. This prevents splattering while allowing the potatoes to cook evenly.
Step 3
Cook about 8 minutes in the microwave for medium-sized potatoes, or until a fork pierces the center easily. If they need more time, continue in 60-second increments until tender.
Step 4
Allow the cooked sweet potatoes to cool to room temperature. Peel and mash with a fork, potato masher or press through a sieve for an extra-smooth texture.
Step 5
Stir in 1 tablespoon of honey, maple syrup or your preferred liquid sweetener. Taste and adjust sweetness to suit your filling needs.
Step 6
Add water a tablespoon at a time until you reach your desired consistency. For mochi or mooncake filling, aim for a thick paste that holds shape; for spreads or steamed buns, add a bit more water for a creamier texture.
Step 7
Optional: fold in 1 tablespoon of melted or softened coconut oil (or butter) to create a glossy, richer paste. This step enhances mouthfeel but can be skipped for a lighter filling.
Step 8
Chill the paste in the refrigerator for 1–2 hours to firm up. Cooling helps the paste hold shape and improves the texture for portioning.
Step 9
Portion the filling using a cookie scoop or spoon. Roll into balls for mochi or shape into disks for mooncakes and other pastries.
Recipe Variations and Optional Add-ins
- Swap purple sweet potatoes for other varieties if needed—the color and texture will change but the method remains the same.
- Use maple syrup, agave or brown rice syrup instead of honey to make it vegan.
- Add a pinch of sea salt to enhance sweetness, or a dash of vanilla for more aromatic depth.
- For a nutty twist, fold in a spoonful of tahini or black sesame paste when cooled.
Purple Sweet Potato Filling for Mochi and Mooncakes
Ingredients
- 2 medium purple sweet potatoes
- 1 Tbsp honey, maple syrup or other liquid sweetener
- Up to 5 Tbsp water, added as needed
- 1 Tbsp coconut oil or butter (optional)
Instructions
- Wash and cook the sweet potatoes until tender (microwave, bake or steam).
- Allow to cool, then peel and mash until smooth.
- Stir in the sweetener, then add water a tablespoon at a time until you reach the desired texture.
- Optionally fold in coconut oil or butter for added gloss and creaminess.
- Refrigerate 1–2 hours to firm up, then portion for mochi, mooncakes or as a spread.
More Filling Recipes Like This
If you enjoy making fillings at home, try experimenting with mung bean paste, white bean paste, cheesecake-based fillings, or spiced pumpkin fillings. Each offers a different texture and flavor profile, and many are simple to prepare using similar methods to this purple sweet potato paste.
