Melt remaining 3 teaspoons butter in saucepan on medium heat,stirring to release browned bits from bottom of skillet. Sprinkle with flour; cook and stir 3 to 4 minutes or until flour is lightly browned.
Gradually stir in broth until well blended. Bring to boil. Reduce heat to low; simmer 10 minutes or until slightly thickened, stirring occasionally. Add vegetable mixture, chicken, pearl onions and peas; simmer 8 minutes or until chicken is cooked through, stirring occasionally.
Meanwhile, cut bread into rounds with 3 inch cookie cutter. Place on baking sheet. Brush bread with oil and sprinkle with reserved seasoning mixture. Bake in preheated 350 degrees oven 10 minutes.