Heat the oven to 350°.
Line a muffin pan with muffin cups.
Trim and chop your strawberries and rhubarb into ¼" chunks and set aside.
In a large bowl, whisk the almond flour, arrowroot, baking soda and salt.
In a medium mixing bowl, whisk the eggs, honey, vanilla and lemon juice or apple cider vinegar.
Pour the liquid ingredients into the dry ingredients and use a spatula to stir them until fully blended and there's no more dry almond flour visible.
Stir in the strawberries and rhubarb.
Scoop heaping ¼-cup scoops into each muffin cup. The muffin cups will be almost completely full.
Evenly sprinkle the sliced almonds on top of the muffins, then sprinkle over the coconut sugar.
Bake for 22-26 minutes, rotating the pan once halfway through the baking time so they all bake evenly, until they're golden brown and the tops look dry. Let cool on a cooling rack, then serve.