Hearty chicken vegetable soup

Name: Hearty chicken vegetable soup
Prep time: 5 min
Cook time: 25 min
Total time: 30 min
Cuisine: European, Italian, Mediterranean
Ingredients: 1 tbsp olive oil; 1 large onion (, finely diced); 4 sticks celery (, finely diced); 3 carrots (, peeled and cubed); 1 large potato (, peeled and cubed); 1 cup (150g) butternut squash (, peeled and cubed); 1 tsp salt; 1 tsp dried thyme or Italian seasoning; 6 cups (1 ½ liters) chicken stock (or broth); 2 pounds (900g) chicken tenders ((mini chicken breasts)); 1 tbsp tomato paste; 1 medium zucchini ((courgette), cubed); 1 cup (150g) corn (fresh or canned); ½ cup (120g) fregola / giant couscous (or risoni pasta); 1 tbsp lemon juice (or to taste); 2 tbsp parsley (, chopped, plus extra to serve); Salt and pepper to season; grated Parmesan to serve ((optional))