One of the most concerning things on par with food to stamina balancing is that the stamina value keeps cascading higher and higher with each cook and as ingredients increase. Limit '100'. We will keep this in mind.
The matter
Having all the commons at 5 seems fairly reasonable.
Uncommon at 10, Rare at 15, epic at 20.
That is a good starting point as far as math goes regarding raw ingredients.
But complex recipes have a fixed cook at 40 for uncommon, 60 at rare and 80 at epic. This causes some issues with Irregular ingredient amounts (maki takes up twice as many (6->40)ingredients in stamina value than (3->20)nigiri) This will make creating balanced recipes very difficult if they have to have the same stamina sum to output!
And the irregular ingredient amounts, plus the ingredients making some sensible sense are a nice and flavourful feature in cooking.
I don't think processed foods need to follow that kind of value pattern as raw ingredients, and this consistency is already broken with a lot of processed ingredients anyway! So anything from the cooking pot can have whatever stamina value as its rarity. Consider that food items with values like 5 are still useful when 'topping' off stamina remainders from high-value foods! So cooking epic value 5 stamina foods could be a neat prospect.
More items in the output
Important note. How to avoid stamina cascading? Consider adding a feature to the cooking pot that gives more items than just one! This way it becomes possible to cook a 10-stamina-value food into two 5-stamina-value foods (as in some recipes with 1 to 1 stamina ratios)
How about these values?
Food should be balanced by the stamina of the ingredients, but the better rarities should be better, right? So how about just adding a stamina multiplier to a rarity output instead of having fixed stamina values?
An item that cooks into a common food 1:1 stamina (why? to get refined ingredients for better recipes! Ie 2 kelp to nori 10 -> 10)
Item cooks into an uncommon food 1:2 stamina (like cooking bettas 5 -> 10)
Cooked into rare 1:3 stamina value (no example? ie 20 -> 60!)
Cooked into epic 1:4 stamina value (like the tuna fin nigiri 20 -> 80)
But what if a recipe calls for uh...1 carrot(20), 1 potato,(5) 1 scrumptious bacon(10) and a pumpkin(5) and cooks into an epic recipe called veggie soup?
That's 40 stamina that when cooked into an epic recipe will give out 160 stamina, overflowing over 100 stamina you can feed a wolf.
Well, what if that recipe gives two servings instead of one? Now you have two 80 stamina servings of delicious veggie soup.
This is why I suggested above to add more items to the output, as it becomes easier to control stamina values.
So if there ever becomes a need to cook higher stamina food value into a lower value, the output can be increased to match the cook rarity.
Need for rebalancing
A lot of recipes would need to be changed. Sugarcane is 5 stamina and sugar is 10. But sugar needs 4 canes to make, so you lose out on 10 stamina. There is no indication that using sugar in recipes is also worth the loss of 10 stamina. As sugar is a common cook recipe, 2 sugarcane to sugar seems more reasonable.
Eggs and other recipes will have to be decreased to 10 if we follow the x1 x2 x3 x4 stamina increase per rarity.
Salmon would have to be decreased to 45, potato soup would then be 105 (ideally I'd remove the russet potato and you'd have a nice 90 stamina meal or split it into 3 meals per 30!), vegetable platter would be increased to 90.
Fish need to be stratified into rarities per fishing location.
The loose ends here are the amounts of ingredients in a recipe, the ease of acquisition of ingredients and the cooking speed. Those need to be addressed as well.
If more commodity crops are added to grow (like cotton) fewer fields may be used to grow food.
If more stamina-draining activities are added, this will also affect stamina balance.
What would an epic stamina stamina recipe look like? purple carrot(20) + russet potato (5) + butter (10) + red raspberry (10) + river salmon (5) = 50 stamina
50 x 4 epic multiplier = 200 stamina: rich salmon roast. That could theoretically spit out 40 5 stamina times, but that would be so extreme! Realistically this recipe would give two roasts with a value of 100 stamina.
If an epic recipe could be light. Carrots + butter = buttered carrots valued at 100 spitting out 20 -> 5 stam value ingredients
(please do not make a recipe spit out 20 buttered carrots, this is just theory-crafting to test the limits of this system of balance ='D)
Any numbers go!
The x1 x2 x3 x4 is a suggestion that may not necessarily ring true.
They can be replaced with any numbers.
x1 x2 x4 x8 is just as consistent as x1 x2 x3 x4, but the boon between epic foods is now just so much greater in one than in the other.
The food values of raw ingredients acquired don't necessarily need to be 5,10,15,20 stamina either...
What matters is that they're consistent with each other.
This has to apply to the pebble values of these foods as well!
So once a decision is made, it can be applied to every single food item and recipe unanimously.
Conclusion
With this spreadsheet method, when new recipes are added, they can be simply balanced by the stamina values of those ingredients according to what rarity it cooks into, and divide the stamina and increase the output if it overflows over 100 stamina. No need to gauge and eyeball!
Math is a dear friend in game design.
I hope this suggestion helps the staff balance stamina and food.