Thoroughly wash the romaine lettuce under cold running water, shake off excess moisture, chop into bite-sized pieces, and place in a large salad bowl.

Rinse the cherry tomatoes and slice them in half, adding to the salad bowl.

Peel the cucumber, dice it, and add to the bowl along with the bell pepper, carrot, radishes, and red onion, then toss gently.

Slice the avocado, remove the pit, scoop the flesh, and dice, folding it into the salad mixture.

Sprinkle sunflower seeds over the salad and crumble feta cheese if desired.

In a separate bowl, whisk together the olive oil, apple cider vinegar, Dijon mustard, honey or maple syrup, garlic powder, and a pinch of salt and pepper until well combined.

Drizzle the dressing over the salad and toss gently to combine.

Garnish with freshly chopped parsley and serve immediately.