I think the "secret" ingredient would have to be tomatoes. Or maybe it won't be a sweet pie but a savory pie with cheese, tomatoes, herbs, etc. Those are all pretty humble ingredients. Here are the meanings of some herbs (from the Internet)
Basil = Love
Bay = Fame
Chamomile = Wisdom
Chervil = Serenity
Chives = Usefulness
Dill = Good cheer, Survival
Fennel= Grief, Endurance
Lavender = Devotion
Marjoram = Joy
Mint= Refreshment
Parsley = Merriment
Rosemary = Remembrance
Sage = Wisdom
Santolina = Virtue
Savory = Interest
Scented Geranium = Happiness
Sweet Woodruff = Humility
Tansy = Hostility
Tarragon=Permanence
Thyme = Daring
Sounds like sweet woodruff should be in it if possible (we have lots of it growing in our Michigan yard). But that's not as easily available. But basil (love), chives (usefulness), dill (good cheer/survival), geranium (happiness), thyme (it takes courage to eat humble pie), sage (wisdom) all seem to fit well with humble pie and are easily available.