Preheat the oven to 415 degrees F. Spread the carrots on a baking sheet, drizzle with avocado oil, and sprinkle with sea salt. Use your hands to toss everything together so that the carrots are fully covered in oil. Roast 25 to 35 minutes, until golden-brown and somewhat wrinkly. Remove from the oven and allow carrots to cool.
5 minutes before the carrots have finished roasting, spread the pumpkin seeds on a baking sheet and place in the oven for 3 minutes, or until they begin turning golden-brown and puff up. Remove from oven and allow pumpkin seeds to cool.
While the carrots are roasting, add the ingredients for the dressing to a blender and blend until creamy and well-combined. Set aside until ready to use. Note: You will end up with more dressing than you need - you can store it in a jar in the refrigerator and use it for future salads or as a marinade.
Add spinach and feta to a large serving bowl. Toss in desired amount of dressing. Serve salad with roasted carrots and pumpkin seeds.