This Ninja SLUSHi Vanilla Protein Milkshake is the perfect way to satisfy your sweet tooth while fueling your body! Made with a vanilla and protein peanut butter cups, this shake blends up into a frosty, indulgent slushie that’s perfect for post-workout recovery or a guilt-free treat. Best of all, it comes together in just minutes using the Ninja SLUSHi machine or a regular blender.
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Key Ingredients
Each ingredient in this is carefully chosen to create a thick, creamy, and satisfying shake that delivers both flavor and protein power.
- Milk – Acts as the base for the milkshake, providing creaminess and helping blend all the ingredients smoothly. You can use dairy or a plant-based alternative to suit your preference.
- Sugar or Sweetener – Enhances the sweetness of the shake, balancing the protein flavors. Adjust the amount to your liking or swap for a sugar-free alternative for a lower-carb option.
- Liquid Vanilla Protein Shake – Adds a rich vanilla flavor while boosting the protein content, making this milkshake not just a treat but also a great post-workout or meal replacement option.
- Protein Peanut Butter Cups – The ultimate add-in for indulgence! These bring a delicious peanut butter-chocolate twist while adding even more protein, making your shake taste like a dessert with a boost of protein.
How to Make Ninja Slushi Vanilla Protein Milkshake with Peanut Butter Cups
Detailed measurements and full instructions can be found in the recipe card at the bottom of this post.
- Combine milk and sugar or sweetener in a cup or glass and stir until the sugar or sweetener has dissolved.
- Add the sweetened milk and liquid protein shake to the Ninja SLUSHi machine. Power the machine on and press milkshake.
- Allow the machine to process.
- Once the cycle is complete, place a cup under the self-serve spout and pull the handle to dispense about half of the milkshake. Sprinkle in half of the peanut butter cups and stir. Continue to fill up the milkshake. Add the remaining peanut butter cups and stir.
How to Use a Regular Blender
You will need to toss in ice for the thick texure, anywhere from 1-3 cups. Add the ingredients to the blender and blend until smooth. Add additional ice as needed in order to thicken it up.
Both the Ninja SLUSHi machine and a regular blender can make a protein milkshake, but they work differently and produce slightly different textures. The Ninja SLUSHi machine slowly freezes and scrapes the mixture, resulting in a light, airy, and creamy consistency. It keeps the milkshake thick and frosty without over-blending, which can sometimes happen with a blender.
Blenders offer more ingredient flexibility. Blenders can handle add-ins like frozen bananas, Greek yogurt, or nut butters without issue.
Frequently Asked Questions
Add 1-2 tablespoons more syrup or sugar and restart the cycle.
It takes about 15-45 minutes, depending on the sugar content and starting temperature of your coffee. It took mine 20-25 minutes.
Use a liquid vanilla protein shake for the best results. You can use store-bought ready-to-drink shakes or blend a scoop of your favorite vanilla protein powder with milk or a milk alternative.
Yes! Regular dairy milk, almond milk, oat milk, or any milk alternative will work. Choose the one that matches your dietary needs and taste preferences.
Yes, if you are using sugar-free ingredients. You will need something like monkfruit, allulose, or sugar.
This milkshake is best served immediately for that perfect texture. If you need to prep ahead, you can blend the ingredients and freeze them, then re-blend when ready to serve.
Try adding a banana for creaminess (must be blended and smooth), a spoonful of Greek yogurt for extra protein, or a handful of spinach (must be blended and smooth) for a nutrient boost.
Absolutely! You can swap them for chocolate chips, cocoa nibs, or even a spoonful of peanut butter to keep that chocolate-peanut butter vibe going.
Pour into a glass, top with whipped cream if desired, and maybe a sprinkle of crushed peanut butter cup pieces for a fun garnish. Enjoy with a wide straw or spoon to savor every slushie sip!
Substitution and Add-ins Ideas
To ensure a smooth and creamy milkshake, any solid or whole ingredients must be blended before adding them to the machine. The Ninja SLUSHi works best with liquid-based ingredients.
- Peanut Butter or Almond Butter
- Protein Powder (Vanilla, Chocolate, or Peanut Butter Flavor)
- Greek Yogurt
- Unsweetened Cocoa Powder
- Mini Dark Chocolate Chips
- Sugar-Free Chocolate Syrup
- Crushed Protein Bars
- Bananas
- Strawberries or Blueberries
- Freeze-Dried Fruit Powder (Strawberry, Raspberry, or Banana)
- Granola or Crushed Graham Crackers
- Toasted Coconut Flakes
- Chopped Nuts
How to Store
You can store leftovers in the machine, but you need to keep the machine running to maintain the frozen texture for up to 12 hours. If you turn it off, the milkshake will melt.
If you want to store leftovers outside of the machine, store them in an airtight container in the freezer. It will keep well up to a month. For short term storage, store the shake in an insulated container. Shake or stir well and add a few ice cubes if it has melted too much. Drink within 12 hours for best flavor.
More Ninja SLUSHi Recipes
Ninja Slushi Coffee Frappé (Vanilla Caramel)
Ninja Slushi Strawberry Lemonade Slush
Ninja Slushi Vanilla Protein Milkshake with Peanut Butter Cups
Want to save this recipe for later?
I’ll email it to you, so you can come back to it later! You will also get our free digital cookbook with 30-Minute One-Pot Recipes and weekly recipes and tips.
Equipment
Ingredients
- 1/2 cup milk Any milk, I used almond milk. Chilled if possible.
- 1-2 tablespoons sugar or sweetener
- 10-12 oz liquid vanilla protein shake Chilled if possible. You can also combine protein powder with 10-12oz of water.
- 1-2 protein peanut butter cups Diced into small pieces.
Instructions
- Combine the milk and sugar or sweetener in a cup or glass and stir until the sugar or sweetener has dissolved.
- Add the sweetened milk and liquid protein shake to the Ninja SLUSHi machine. Power the machine on and press milkshake.
- Allow the machine to process. Let the machine run for 15-45 minutes, depending on the sugar content and temperature of the liquid. Mine took 20-25 minutes.
- Consider a large glass for serving because the milkshake will turn out really thick and creamy.Once the cycle is complete, place a cup under the self-serve spout and pull the handle to dispense about half of the milkshake. Sprinkle in half of the peanut butter cups and stir. Continue to fill up the milkshake. Add the remaining peanut butter cups and stir.
Notes
Nutrition
Nutrition Data
Macros are provided as a courtesy and should not be construed as a guarantee. This information is calculated using MyFitnessPal.com. To obtain the most accurate nutritional information in a given recipe, you should calculate the nutritional information with the actual ingredients used in your recipe, using your preferred nutrition calculator. You are solely responsible for ensuring that any nutritional information provided is accurate, complete, and useful.