Preheat oven to 350F. In a small bowl, whisk 1 cup non-dairy milk, lemon juice, 3 tbsp maple, light brown sugar & 1-2 tsp vanilla together until foamy and bubbly. In a large bowl, whisk flour, cocoa, salt, baking powder, baking soda and chocolate chips (crushed). Pour wet into dry and use a spatula to combine. Spoon into a greased 6-donut pan. Bake 15 minutes. Meanwhile, make icing by whisking the last ingredients together (confectioners sugar, 1 tbsp maple, 1 tsp vanilla and 1-2 tbsp non-dairy milk). Submerge cooked, but cool, doughnuts into icing and let glaze drip off. Transfer to wire wrack for drying.