Preheat oven to 350. Grease a standard 9x5 loaf pan.
In a mixing bowl, combine the flour, cornmeal, baking soda, salt, and spices. Set aside.
In the bowl of a stand-mixer fitted with the paddle attachment, mix the eggs, sugars, oil, yogurt, and pumpkin until smooth. Add the dry ingredients in two batches, mixing until just blended after each addition. Scrape the batter into the prepared loaf pan and smooth the top. Sprinkle with sunflower seeds to cover.
Bake 50-60 minutes or until completely set and cooked through. Let cool on a wire rack for 10 minutes, before turning out of the pan to cool completely.
To make the Orange Cream Cheese: mix together the cream cheese, sour cream, sugar, and orange zest until smooth and well-combined (I used the stand-mixer again). Transfer to a small serving bowl (or refrigerate, covered, if making ahead).
To serve: Slice the bread and serve with Orange Cream Cheese.