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This Birthday Cake Protein Shake tastes like cake batter straight from the bowl, blends up thick and creamy in minutes, and delivers serious protein without feeling like a compromise.

If you want that nostalgic birthday cake flavour whilst staying within your macros then this is the recipe for you.

It pours into the glass like a classic diner milkshake, holds its shape, and looks downright festive with whipped cream and rainbow sprinkles on top.

This Birthday Cake Protein Milkshake delivers rich cake batter flavor with a thick, creamy texture and an impressive 60g protein, making it a high-protein dessert that tastes indulgent but blends up in minutes.

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It’s the kind of shake that makes you forget you’re drinking something built around macros and tastes like the perfect dessert.

Why You Will Love This Recipe

Delivers a massive 60g of protein in one shake
Thick, creamy milkshake texture without ice cream
True birthday cake flavor thanks to cake batter extract
Easy to customize for calories, carbs, or sweetness
Ready in under 5 minutes with a single blender
Great as a post-workout shake or dessert replacement
Can be split into two servings without losing texture

This recipe is high protein, lower fat, and flexible depending on how strict your goals are.

While it isn’t keto due to the skim milk and sprinkles, it fits well into a low-fat, macro-friendly lifestyle.

Net carbs are clearly defined, and I’ll walk you through how to reduce them further if needed.

It’s also a great make-ahead option for busy days, with storage tips below.

Ingredients You Need

Ice (2 cups)

Ice is what gives this shake its thick, milkshake-style body. Do not reduce it unless you want a thinner drink. Crushed or cubed both work.

Skim Milk (1 cup / 240 ml)

Keeps calories low while providing volume and blendability. You can substitute unsweetened almond milk to lower calories and carbs, but the shake will be slightly less creamy.

Fat-Free Vanilla Greek Yogurt (½ cup / 110 g)

Adds creaminess, tang, and extra protein. This is not optional if you want that rich texture. Regular yogurt will increase fat and calories.

Whey Protein Powder (1½ scoops / 45 g)

Use a high-quality vanilla whey that blends smoothly. Avoid casein-only powders here, as they can make the shake overly thick and gummy.

Zero-Calorie Sweetener (1 tbsp)

Adjust to taste depending on your protein powder. Granulated or liquid both work.

Xanthan Gum (½ tsp)

Critical for thickness. Too much will make the shake gluey, so measure carefully. Do not skip unless you’re okay with a thinner consistency.

Cake Batter Extract (1 tsp / 5 ml)

This is what makes the recipe work. Vanilla extract will not give the same flavor. You’ll find this near vanilla extract in most grocery stores.

Rainbow Sprinkles (1 tbsp / 15 g)

Adds texture and classic birthday cake vibes. These do add carbs, so measure accurately.

Whipped Cream (2 tbsp / 5 g)

Optional but recommended. A little goes a long way for presentation and mouthfeel.

Step-by-Step Directions

Add the ice, skim milk, Greek yogurt, whey protein, sweetener, xanthan gum, and cake batter extract to a high-powered blender.

Blend on high until completely smooth. The mixture should be thick but pourable, similar to soft-serve.

Pour the milkshake into a large glass.

Stir in the rainbow sprinkles gently so they’re evenly distributed.

Top with whipped cream and additional sprinkles if desired.

Serve immediately for best texture.

Tips for Success

Measure the xanthan gum carefully. I once doubled it by accident, and the shake turned into a pudding that refused to pour.
Always add xanthan gum before blending, not after. Dumping it in late causes clumping.
Use a blender strong enough to fully break down the ice. Weak blenders will leave chunks.
If the shake is too thick, add milk one tablespoon at a time.
For a colder, thicker result, chill your glass beforehand.
Do not skip the cake batter extract. Vanilla alone will taste flat.

Frequently Asked Questions

Is this Birthday Cake Protein Milkshake keto?

No. This recipe is not keto due to the skim milk and sprinkles. However, it is high protein and relatively low fat. You can reduce carbs by using almond milk and fewer sprinkles.

How many net carbs are in one shake?

Approximately 30g total carbs per full shake, with minimal fiber. If split into two servings, net carbs drop significantly per portion.

Can I make this ahead of time?

Yes. Store in an airtight container in the fridge for up to 24 hours. Shake or re-blend before serving.

Can I freeze this?

You can freeze it into popsicle molds for a protein ice cream-style treat. Thaw slightly before eating for best texture.