Jamie Oliver's Purple Potato Salad

I went to Baguio City last Panagbenga and we bought 10 kilos of potatoes for only Php 380. Now, I am thinking of making potato salad on Saturday, but I wonder what is crème fraîche or fromage frais. I am really dying to have a try of Jamie Oliver's recipe, but I think I cannot find Jamie's cream here in the Philippines. I need a substitute for it.

By the way, here is Jamie Oliver's Purple Potato Salad:
- 6 tablespoons extra virgin olive oil
- juice of 1–2 lemons, to taste
- 250g crème fraîche or fromage frais
- 500g baby new potatoes
- 500g purple potatoes
- sea salt and freshly ground black pepper
- a bunch of radishes, finely sliced
- a handful of fresh mint leaves, chopped
- a handful of fresh chives, chopped

Make the dressing by mixing together the olive oil, lemon juice and crème fraîche or fromage frais. Cook the potatoes in plenty of boiling salted water for around 20 minutes until tender, and drain well. When the potatoes are cool enough to handle, rub off the skins with a knife and slice into bite-size pieces. Mix with the dressing, then add the radishes and herbs and season well to taste.