In a large pot of boiling water, blanch kale for 2 minutes. Add basil leaves for 30 seconds and remove everything with a slotted spoon to a colander and run under cold water; set aside to drain.
Do not discard water – keep it in the pot to boil the spaghetti.
Combine kale and basil leaves in a blender along with Parmesan cheese, yogurt, oil, almonds, lemon juice and salt. Pulse to break down and combine. Scrape down sides and blend until smooth; set aside.
Preheat oven to 425ºF (220ºC) oven and line a small baking sheet with parchment paper.
In a large bowl, toss together grape tomatoes, garlic, oil, oregano and ¼ tsp (1 mL) each of the salt and pepper. Spread onto prepared baking sheet and roast for 15 minutes or until golden and tender.
In another bowl, whisk together yogurt, Parmesan cheese, egg and remaining salt and pepper; set aside.
Meanwhile, return pot of water to boil and add some salt. Cook pasta for about 8 minutes (or as per package instructions) or until al dente. Measure out ½ cup (125 mL) of the cooking water and whisk into yogurt mixture. Drain pasta and return to pot.
Add roasted tomato mixture along with yogurt mixture and toss to combine. Stir in half of the creamy kale pesto and serve in shallow pasta bowls. Dollop with more pesto on top and more grated Parmesan if desired.