1. Place the potatoes in a large bowl and cover with cold water; set aside for 15 to 20 minutes, changing the water once.
2. Heat the oven to 425F/220C/Gas 7.
3. Drain and rinse the potatoes and dry with a kitchen towel; place in a bowl and toss with the oil, garlic, paprika, oregano, thyme, red pepper flakes, and lemon juice.
4. Transfer to a baking dish, large enough to hold the potatoes in a single layer. Bake for about 15 to 20 minutes, or until cooked through and golden brown.
5. Meanwhile, blend all sauce ingredients, adding enough water to get a sauce consistency.
6. Serve the potatoes drizzled with the sauce and with lemon wedges on the side. Enjoy!