Preheat oven to 400°F and prepare a muffin tin with liners or grease well. Chop frozen raspberries into smaller pieces, divide evenly into two bowls, and return to the freezer.
In a large mixing bowl, whisk together flour, sugar, and baking powder. In a separate mixing bowl, whisk together dairy-free yogurt, oil, vanilla extract, plant milk mixture, and lemon zest until smooth. Pour wet ingredients into dry ingredients and mix until just combined. Do not overmix.
Remove raspberries from the freezer and gently fold into the batter.
Divide batter evenly into muffin cups.
Bake for 24 minutes, or until muffins are set and a toothpick comes out clean.
Let cool before serving.