Cook the potatoes:

1. Cut each baby potato in half (for larger baby potatoes, cut into quarters). If using full-sized waxy potatoes, cut them into about 1 1/2 inch chunks.
2. Place the potatoes into a large saucepan. Fill with cold water until potatoes are covered by about 1 inch. Bring to a gentle boil over high heat and add a generous amount of salt to the water (about 1 tablespoon). Gently boil the potatoes until fork-tender, about 8 - 9 minutes. During the cook time, turn the heat down as necessary to maintain a gentle boil.
3. When the potatoes are cooked, drain and rinse them with cold water to cool them down a bit, and drain again well (potatoes should still be warm, but not steaming hot). Set potatoes aside if still prepping the other ingredients (steps 4 - 5).

Prep the vegetables and make the dressing:

1. While the potatoes are cooking, prep the veggies: slice the onion, chop the dill, and mince the garlic. Set aside.
2. To a large bowl, add the minced garlic, extra-virgin olive oil, lemon juice, red wine vinegar, grainy mustard, dried oregano, and 1/2 teaspoon salt. Whisk to combine.

Assemble the salad:

1. Add the cooked potatoes, drained tuna*, thinly-sliced onion, chopped herbs, and capers to the bowl.
2. Stir gently to combine. Taste the salad and add more salt if needed. The potato salad can be served warm right away, or at room temperature, or cold.