In a large bowl squeeze the juice of a lemon. Remove the tough, outer leaves from the artichoke (should be about 3-4 layers of leaves) or until you reach leaves that are pale yellow. Cut in half or leave whole (when you cut it in half , cut out the choke using a knife (it looks almost furry, actually if you get artichokes fresh enough there might not even be a choke). The stem should be cut from the artichoke, leave about 2 - 3 inches and clean, (trim with a knife peeling off the tough outer layer) put cleaned artichoke and stem into bowl of lemon water (this keeps them from turning brown). Repeat with remaining artichokes.
In a small bowl, mix together mint,garlic,oregano,salt and olive oil, drain artichokes and stems and place in a medium frying pan, cover with oil mixture, add 1 cup of water, mix gently to combine, cover and cook over low to medium heat for approximately 20 minutes or until water has evaporated and artichokes are tender. To die for. Buon appetito!
If you want to use frozen artichokes then do the following - If the artichokes are whole then slice them in half (from top to bottom), place them in a pan cut side up with a tablespoon or 2 of olive oil, and drizzle the mint oil mixture over the artichokes. I would probably use a little less water 1/2 cup to start with (since the artichokes are frozen) and continue with the recipe. If by the time the water has evaporated and they aren't cooked then just add a bit more water and continue cooking.