Leeks a la Betty Burr

Leeks a la Provencale
Betty Burr gave me a wonderful recipe which she calls Leeks a la Provencale. I have used it as is, and altered it for many others. The mild oniony-garlicy leeks, plus the subtle taste of the lemon rind, are super in a lot of combinations, which I hope to catalogue here. When I use it in other combinations, for instance witn fish, I often leave out the olives.
Here goes:
Leeks a la Provencale
1 1/2 lbs leeks, cut in 1/2 inch slices, three tomatoes cut in quarters, 16 black olives stoned, 1/4 cup olive oil, rind and juice of one juicy lemon.
Put leeks, salt and pepper into warm oil. Cover pan and simmer 10 minutes. Add other ingredients and cook slowly 20 minutes.
Serve cool.