Lentil Piyaz (Marinated Turkish Salad)

Ingredients

2 cups (500 mL) red onion, halved and sliced thinly

2 Tbsp (30 mL) garlic, minced

½ cup (125 mL) white wine vinegar

1 quart (1 L) whole red lentils, cooked and drained

1 quart (1 L) Roma tomatoes, cut into thin lengthwise wedges

½ cup (125 mL) flat leaf parsley, roughly chopped

1 Tbsp (15 mL) sumac

¼ cup (60 mL) extra virgin olive oil