Protein/Energy Bars (T-rex's 'grey Cubes')




Inspired by this comic: (note the alt text), a busy life, and some internet-research on homemade energy-bars, these bars are intended to keep you going until you finally get to sit down to eat. Simple and easy for the “people who get hungry and don’t care about food, but also don’t want to die”*

*Sadly, like all energy bars, not actually suitable to keep you alive as a sole nutritional source. Maybe add an apple.

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Step 1: Ingredients

1 cup   nutella
1 cup   peanut butter
1 cup   protein powder
½ cup  oats**
½ cup  rice flour
1/3 cup  almonds
5 Tbs   condensed milk
1/3 cup  sunflower seeds
¼ Tsp  salt

I probably don’t need to say it, but you can of course substitute the choice of gluten free flour, seeds/nuts, add dried fruit, add chilies, go for all-PB or all-Nutella, and generally have fun with it. Just to note, rice flour from an Asian market can be a lot cheaper than a fancy all-purpose gluten-free flour mix from a super market. 

Other things you may need or want:
Oven, mixing bowl, cookie sheet, baking/wax paper, press (actual or creative hack)

**Make sure they are gluten free, and if you have trouble with oats, just swap for more flour.

Step 2: Mix to a Pressable Consistency

Combine flour, protein powder, and salt
Mix in nut butters
Mix in condensed milk by the Tbs until the mix reaches a firm-but-sticky consistency
Add in nuts and seeds

Note: If you did want to precisely measure out the peanut butter/nutella, a pre-floured cup can be very helpful. Otherwise, estimating the amount of nut butter and adjusting the consistency with condensed milk is probably easier.

This is a good time to preheat the oven to 175 C / 350 F. 

Step 3: Shape 'em

If you are a sushi fan with an oshizushi press or have any have any other food-press around, these work very nicely.

Cubes or spheres can be shaped by hand.
A press can be made out of common items, such as a lunch box and a small cutting board. Make sure to use baking/wax paper on top and bottom to simplify getting the cubes back out.

Step 4: Bake 'em

Put “grey cubes” on a cookie sheet (oiled or with baking paper)

Bake cubes for 30 min at 175 C / 350 F

Step 5: Eat 'em


Recipe makes ~ 15 x 50g “grey cubes”*

Information    per cube    per 100g

Calories         230             460
Protein           12g             24g
Carbs             15g             30g
Fat                  13g             26g
Fiber               2g               4g

Here in Germany, the cost of making one of these is 0.30 EUR, which is less than a 7th of the cost of a cliff bar (for comparable grams and Calories).

Shelf life is at least two weeks (the current record for how long until they have all been eaten).

*with the recipe as is, I must apologize that the cubes will not actually be grey =P

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    18 Discussions


    3 years ago

    I wonder whether some applesauce would make them healthier.


    6 years ago on Introduction

    These sound great, but oats are in no way gluten free, and you cant get them gluten free, but you could try quinoa instead.

    2 replies

    Reply 6 years ago on Introduction

    Thanks for pointing this out, but I'm going to have to beg to differ. From what I've read, many strains of pure oats do not cause a reaction in most Coeliacs in properly controlled scientific studies. Besides wikipedia, you can see,,
    [and more, but those were free full text]
    If you are not among those who have no trouble with oats, then of course, please do substitute with quinoa, that's probably better texture than just more rice flour as I previously suggested. =)


    Reply 4 years ago

    Bob's Red Mill sells oats guaranteed not cross-contaminated by other crops nearby or machinery. Oats are totally gluten free.


    6 years ago on Introduction

    Reminds me of a solid version of soylent (which has a lot of thought applied about micro-nutrients).

    Also, if you apply a little bit of flour after you've baked them they will stick even less and look a bit more grayish :)

    2 replies

    5 years ago

    Making these tonight! I just made my own brown rice flour for them


    6 years ago on Introduction

    Power Hungry by Camilla Saulsbury has some recipes like this that are super easy.


    6 years ago on Introduction

    This would be great for extra energy! BUT its an artery killer. I'd probably get rid of nutella (way too much trans fats) and just use cocoa powder and cocoa butter (plain chocolate in other words). Ditto for condensed milk, also has a lot of trans-fats due to heating/evaporation of milk. May be up the nuts (macadamias are better fat-wise) and use a little dry fruit for sweetness, so you can have high energy and good health. (yes I am a nutritionist)

    1 reply

    Reply 6 years ago on Introduction

    These are good tips for making them healthier. I admit we personally haven't been exceptionally concerned with this, and have tailored them to our own back-from-running-lets-eat-whatevers-in-the-kitchen life style. =)
    Both cocoa and dried fruit have been used before (turned out well, but weren't on hand the other day), of course, one needs to add some liquid for the consistency. I'm guessing normal milk would work.


    6 years ago on Introduction

    Have you tried adding caffeine or any other energy blend, or are you relying on the protein and carbs for the energy?

    1 reply

    Reply 6 years ago on Introduction

    Not yet, thanks for the idea. :-)
    I can imagine a coffee version would be nice. If you try it, please let us know how it turned out.


    6 years ago on Introduction

    oops! sorry, I didn't read to the end before i posted that...


    6 years ago on Introduction

    Have you calculated the grams protein, carbohydrates and fat per ounce or kg ? This would be helpful to know for those of us on a perpetual diet :)