This would give us an infinite source of mid-quality food for cows that are of reasonable applicability. Currently Cows have the appetite of a Colombian Mammoth for minimal return. To just further that analogy for humor's sake I should mention there is a reason they are extinct! Trees are softcapped at 100-200 with significant achievement difficulties (Constantly remaking tables, localized resources) whereas farmed goods have a much higher and less difficult softcap with less achievement difficultly. THe contrast here is that production of super high quality cows from farmed goods should be unreasonably difficult so I AM NOT SUGGESTING THAT APPETITE BE CHANGED. Rather that lower quality cows be a bit easier to produce.
Alternatively or additionally, make grazed grass infinite. It's only Q10 This would be a significantly more balanced game mechanics that would allow us to reasonably make butter for baked goods. As it stands I promise you will never see another carrot cake, muffin, or apple pie, ever. The alternatives are just too significantly more valuable than these items.
Even so, Maybe those items should be buffed so they are worth producing. 2x FEP's would make carrot cakes worth producing at 90+ if the above suggested infinite food sources are added (or the cow diet is reduced to a realistic and practical level of manageability).
Also note that this suggestion is aimed at creating manageable balanced game mechanics fromt he status quo. If there is intent to further softcap farmed goods by making them dependant on some natural , localized or workable resource (like manure) then these suggestions may not be applicable. Of course...that would make the cow diet far more unreasonable anyway so the base of the argument stands for grass but maybe not the leaves.
Regenrating grass would also be reasonable and is proabbly the best way to do this. Making a game mechanic that forces people to allot a certain amount of space per cow while also giving an infinite source of low Quality food.