Prep: Preheat your oven to 400°F (200°C). Line 12 wells of a muffin pan with parchment liners or lightly grease the pan.
Mix the batter: In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt. Pour in the plant-based milk, oil, lemon juice (or vinegar), vanilla, and almond extract and gently stir to combine. Don't overmix, lumps are totally cool. Overmixing can result in the muffins not rising properly.
Add blueberries: Fold in the blueberries (and any flour they were tossed with).
Top: Divide the batter evenly among the prepared muffin cups. Top each muffin with a few extra blueberries. In a small bowl, mix together the coarse sugar and cinnamon, then sprinkle evenly over each muffin.
Bake: Bake for 20–25 minutes, or until lightly golden and a toothpick inserted in the center comes out clean.
Cool & store: Let cool for at least 10 minutes before removing from the pan. Store at room temperature for 3–4 days, or freeze in an airtight container for longer storage.