Begin by placing the petite white or red potatoes into a medium pot and covering them with cold water. Add kosher salt. Bring to a boil, then simmer for about 15 minutes, until fork-tender.

While the potatoes cool, combine olive oil, red wine vinegar, minced garlic, dry mustard, thyme, oregano, and a pinch of salt and pepper in a jar. Seal and shake until emulsified.

Drain the potatoes and let them cool for 5-10 minutes. Cut into halves or bite-sized chunks, drizzling some reserved caper brine over warm potatoes.

In a large bowl, gather potatoes, olives, sun-dried tomatoes, capers, and red onion. Add fresh dill and pour the dressing over. Toss gently to coat.

Taste and adjust seasoning before serving. Just before serving, sprinkle feta over the salad and let it rest at room temperature or in the fridge for at least an hour.