Tomato, Onion, and Cucumber Salad

INGREDIENTS

• 1 Kirby cucumber, halved lengthwise and thinly sliced
• 1/4 red onion, peeled, halved lengthwise, and thinly sliced
• A generous drizzle of extra-virgin olive oil, about 2 tablespoons
• 2 splashes red wine vinegar
• 5 medium plum tomatoes, halved lengthwise, seeded, and thinly sliced
• Coarse salt and black pepper