Preheat the oven to 375F.
Place the minced onion, garlic flakes, poppy seeds, sesame seeds, black pepper and coarse salt on a plate and mix it all together. Drizzle the chicken tenders with some EVOO, giving them a toss to make sure they are fully coated. Place skewers through each chicken tender lengthwise. Dip each skewered piece of chicken into the seed mixture and turn to coat.
Repeat until all the chicken has been coated then transfer skewers to a nonstick baking sheet and transfer to the oven for 20-25 minutes. Turn them over about halfway through the cooking time.
While the chicken is cooking make the dipping sauce: In a bowl, combine the soft cream cheese and sour cream. Stir in the chopped scallions and season with a little salt and pepper.
Remove the chicken tenders from the oven and serve with the scallion-cream cheese dipping sauce alongside.