1-Preheat the oven to 425℉: Preheat the oven to 425℉.
2-Place the quartered potatoes on a greased: Place the quartered potatoes on a greased or parchment paper-lined baking sheet and roasted them for 35-40 minutes, or until golden brown with tender, fluffy insides.
3-Meanwhile in a large mixing bowl, combine: Meanwhile in a large mixing bowl, combine the onions, cucumber, pistachios, dill and parsley. Give a mix and set aside.
4-In another bowl, combine the mayo, mustard,: In another bowl, combine the mayo, mustard, garlic, lemon, sweetener, salt, pepper, and red chili flakes (if using). Whisk until smooth.
5-Once the potatoes are roasted, let them: Once the potatoes are roasted, let them cool for a few minutes.
6-Toss the potatoes with the dressing, then: Toss the potatoes with the dressing, then pour the chopped veggies over the salad. Gently mix until all is well combined.
7-Serve right away for a warm potato: Serve right away for a warm potato salad or chill in the refrigerator for a cold potato salad.
8-Enjoy: Enjoy!