This is a traditional Sri Lankan dish. Frying the bitter gourd (aka bitter melon in East Asia) takes away the bitter taste (but beware that the dish has a sophisticated bitter undertone - the lime and tomato help with that).
I have never seen bitter gourd in a regular supermarket in the US. I buy mine at my local Patel Brothers, and I'm sure any local Asian market will have them. This is what they look like, raw:
They are about the size of a skinny cucumber pickle.
Recipe:
5 small/medium bitter gourds
1 small red onion, sliced very thin
1 tomato, seeded and chopped
2 green chilis, thinly sliced
lime juice
white vinegar to taste
kosher salt (or whatever kind you have on hand)
Slice bitter gourd into very thin circles/rings.
Deep fry in vegetable oil till crisp and till the vegetables darken.
Place bitter gourd on paper towels to soak up excess oil.
Sprinkle with kosher salt to taste.
Put in bowl and toss with tomato, onion, chili, vinegar and lime juice to taste.
Serve! It is traditionally served with white rice and curry dishes.
