Cook the bacon. Lay slices on a cold skillet, turn heat to medium, and cook until crisp. Drain on paper towels and crumble once cooled.
Hard-boil the eggs. Place eggs in a small pot, cover with cold water, bring to a boil, then cover and turn off heat.
Let sit 10–12 minutes, transfer to an ice bath, peel, and chop.
Prep the chicken. Use leftover or rotisserie chicken, or quickly pan-sear seasoned chicken breasts in olive oil until cooked through. Let rest, then slice or dice.
Mix the dressing. In a small jar, combine olive oil, red wine vinegar, Dijon, garlic, salt, pepper, and oregano. Shake until emulsified.
Taste and adjust salt or vinegar.
Assemble the base. Add chopped greens to a large salad bowl or platter. Drizzle with 1–2 tablespoons of dressing and toss lightly to coat.
Add the toppings. Arrange chicken, bacon, eggs, avocado, tomatoes, blue cheese, and onion over the greens. Keep them in rows for a classic Cobb look or mix them evenly—your call.
Finish and serve. Drizzle more dressing over the top.
Season with a pinch of salt and pepper if needed. Garnish with herbs and a squeeze of lemon, then serve right away.