Preheat the oven to 400 degrees and set out an 8 x 8-inch (or slightly larger) ceramic or glass baking dish.
If using fresh strawberries, skip to the next step. If using frozen strawberries, defrost them and drain off any excess liquid.
Add the strawberries and rhubarb to a large saucepan and cook over medium heat for 3-5 minutes, stirring frequently, until thy start to release liquid. Reduce the heat to medium-low and add the arrowroot, sugar, and cinnamon. Stir and cook for another 5-7 minutes, stirring frequently, until the fruits are tender and the liquid is very thick and saucy. Transfer the mixture to the 8×8-inch baking dish and set aside.
In a large bowl, add the COBBLER ingredients and mix well with a rubber spatula. It should be a little crumbly but moldable with your hands. If looking too crumbly, add more almond milk; if too wet, add more flour.
Using an ice cream scooper, scoop about 1 ½tbsp of the dough and top the berries with the cobbler dough. DO NOT press down on biscuits. They should look rustic!
Place the cobbler on the middle rack and bake for 30-35 minutes. The fruit should be bubbling and the cobbler biscuits golden brown. Let cool for at least 10 minutes before serving to help the fruit thicken.
Serve with whipped cream or vanilla ice cream, mint (optional), and enjoy. Store cooled leftovers covered in the refrigerator for up to 4 days. Biscuit dough can be frozen for up to 1 month before baking and added when ready to bake.