Heat the oven to 350 degrees. Allow the oven to reach full heat before the filled pan goes in so the loaf begins setting evenly.
Coat a large loaf pan with non stick cooking spray, or line the bottom with parchment paper. The prepared pan helps the delicate flourless loaf release without tearing.
Place the room-temperature cream cheese and avocados in a blender. Start with softened cream cheese so the mixture can become creamy rather than lumpy.
Blend until the avocado and cream cheese form a smooth green puree. Stop only when no pale cream cheese pieces or avocado flecks remain.
Add the eggs and Everything bagel seasoning, then blend just until combined. The batter should look glossy and uniform without streaks of egg.
Pour the batter into the prepared loaf pan. It should settle into an even layer with a soft, pourable consistency.
Scatter a bit more Everything bagel seasoning over the surface. The topping will toast as the loaf bakes and create a fragrant, speckled crust.
Bake for 30 minutes at 350 degrees, checking the center with a toothpick before removing the loaf. The top should look lightly puffed and spring back slightly, and the toothpick should come out clean or with dry crumbs.
Let the loaf rest on a wire rack before slicing, then serve warm with a pat of butter. The interior will feel firmer after resting, which helps each slice keep its shape.