Vegetable Confetti Soup

• 12 mushrooms
• 4 carrots
• 2 onions
• 2 trimmed fennel bulbs
• 2 zucchini (cut into)
• 1 3/8 in dice
• 1 pepper (red)
• 2,400 ml chicken stock
• 16 ml vegetable oil
• 2 gr tarragon (dried)