In a large pot, heat olive oil over medium heat. Add onion and garlic and sauté for 5 to 7 minutes. Add the broccoli and cook for a few more minutes, before adding the potatoes and vegetable broth. Bring to a boil, then reduce heat to low and cover. Let the veggies cook for 20 minutes, or until the potatoes are tender.
Use an immersion blender to blend the soup right in the pot, or transfer it to a stand blender in batches. Do not fill the blender all the way to the top (liquid will be very hot!), remove the center part of the blender top, and cover with a folded dish towel while blending to let steam escape. Transfer to a bowl and repeat with the remaining soup.
Once the soup is smooth, stir in the frozen peas and Greek yogurt.
Heat the soup for 5 to 7 minutes over medium heat, so that the peas soften, before serving. Garnish with additional peas, a dollop of yogurt, or a sprinkle of shredded cheddar cheese. Enjoy!
Store leftovers in an airtight container in the fridge for up to 5 days. Reheat in a small saucepan on the stove over low-medium heat, stirring occasionally. Or reheat in a bowl in the microwave for 1.5-3 minutes on high.
Freeze the soup in airtight containers for up to 3 months. Thaw in the fridge before reheating.