Microwave potatoes for 6-8 minutes, until a fork can be inserted with little resistance and potatoes are slightly soft. Alternately, place potatoes in a large pot of cold water, cover and bring to a boil. Lower to a simmer for about 4 minutes.
Once potatoes are cool to the touch, if they are medium or large size, cut them into large bite sized chunks.
Preheat oven at 350 degrees.
In a bowl, toss potatoes with olive oil, salt, half of the lemon juice, thyme and chili flakes (if using).
Place potatoes in single layer on parchment- or foil-lined sheet pan, and roast until lightly browned and tender, about 30-45 minutes.
An alternate method, is to broil the potatoes until browned and tender, but be careful not to burn them.
Remove potatoes from oven, return potatoes to bowl and toss with remaining lemon juice and lemon zest before serving.