Preheat oven to 400ºF.
In a bowl, combine 2 tbsp olive oil, cumin, coriander, garlic and salt. Set aside.
Line a large baking sheet with parchment paper.
Arrange the sweet potatoes and carrots in a single layer on the baking sheet.
Drizzle with olive oil mixture and toss to coat.
Roast the vegetables, turning once, for 25 to 30 minutes or until tender.
Remove from the oven and set aside.
In a bowl toss the arugula and remaining olive oil.
Use a spoon to scoop out the avocado flesh and chop it into ½ inch cubes.
Place in a bowl and add lemon juice.
Sprinkle with chopped hazelnuts and sesame seeds and gently toss to coat.
To serve, divide the arugula between serving plates.
Top with roasted vegetables and avocado mixture.
Season to taste.
Serve with lemon wedges.