Heat oil in a large sauce pan over medium-high heat, add onion and 1/4 tsp. of salt and pepper and cook 5-7 minutes, stirring often.
Add broth, thyme, and Parmesan rind and bring to a boil. Reduce heat to medium and simmer, stirring occasionally until the liquid is slightly reduced and the rind is very soft, 10-12 minutes. Add the peas and continue cooking 3 minutes.
Remove the thyme sprigs and Parmesan rind. Puree the mixture in a blender in batches until very smooth. Serve drizzled with yogurt and paprika oil, and top with Parmesan crisps.