First, a little prep: preheat that oven to 350°F/177°C. Then, place cupcake liners (aka paper baking cups) in nine spots of your muffin tin.
Then, zest one whole medium-sized lemon using a microplane or the side of your box cheese grater with the smallest holes. Set the zest aside for now.
While you have that lemon handy, cut it in half width-wise and extract the juice so you have two tablespoon's worth. Add this juice to your blender base (I used the bullet type) along with the nondairy milk and set aside. You may notice the milk start to curdle a bit, but don't fret! This is actually what you want.
Next, add the dry ingredients to a medium-sized mixing bowl and stir until combined
Take 1/2 cup roughly chopped dates and add them to the blender base containing the milk and lemon juice. Add the vanilla extract as well, and blend on high for a good 30 seconds to a minute or until the contents are completely liquified or at least decently smooth.
This next part is super important: add the liquid concoction to the mixing bowl containing the dry ingredients and very gently, stir the ingredients together until just combined. Do not overmix.
Then, add 1 cup of blueberries to the mixture and very gently fold them in.
Spoon the batter into the lined spots on your muffin tin. To prevent overflowing muffins, only fill each spot about 2/3 full. Then, add 1-3 blueberries to the top of each muffin-to-be, to ensure each one shows the world that it is indeed, a blueberry muffin!
Finally, it's time to make the topping. Add the butter chunks, sugar and flour to a small bowl and mix it all together with a fork or your fingertips until all of the flour is mixed in with the butter pieces. Then, evenly distribute the topping mixture to the top of each muffin. This topping is fantastic because it adds a little crumbly, salty-sweet goodness to each muffin - YUM!
Bake the muffins in your preheated oven for 19 - 20 minutes. As soon as they come out, make sure they're done by inserting and removing a toothpick down the center of a couple different muffins. The toothpicks should exit the muffins batter-free (blueberry smudges don't count!)
Allow the muffins to cool for 5-10 minutes before removing them from the tin. Feel free to admire the beauty of these muffins while you wait.