Tear the lettuce into smaller pieces. Spin the lettuce dry in a salad spinner (optional, but recommended).
Wash all the vegetables and dry them. Cut the cucumber into slices, bell pepper into strips, tomatoes in half.
Toast pepitas and sunflower seeds in a dry pan, until lightly browned and fragrant. Be careful not to burn them – when they smell nutty and are lightly browned remove them immediately from the pan.
Make the dressing: add all the ingredients into a jar, close the lid and shake vigorously until well-combined (you can also whisk the ingredients in a bowl).
Toss the lettuce with chopped vegetables, toasted seeds, and yogurt dressing until combined. Season with salt and pepper to taste.
Enjoy!