For the Crème Fraîche:
Add heavy cream and buttermilk to a wide mouth pint jar. Set the lid on slightly ajar to allow some air in. Leave the jar out at room temperature overnight, 8-12 hours.
Tighten the lid and refrigerate 24 hours.
Stir in the Dukkah. The crème fraîche can be made ahead and will keep in the refrigerator for 2 weeks.
For the Spring Spaghetti:
In a large sauté pan over medium heat, combine the olive oil, garlic and lemon paste. Cook until fragrant and the garlic is softened, 2-3 minutes.
Add the asparagus and peas, and continue cooking until the asparagus is tender and bright green, 2-3 minutes more.
Add the cooked spaghetti and stir to coat with the sauce and vegetables.
Remove from heat and add the crème fraîche and parsley. Stir until combined.
Plate the spaghetti and garnish each dish with a soft poached egg and a final sprinkle of Dukkah!