In a saucepan, melt butter over low heat. Remove from heat and reserve. In a small bowl, sift or stir together flour, baking soda, cinnamon, nutmeg, allspice and salt. Set aside.
In a large bowl, whisk the ground flax seeds with warm water till it forms an egglike mixture. Alternatively, you can microwave the flax-water mixture for 15-30 seconds to achieve the same effect, then add the mixture to a large bowl.
Using a wooden spoon, mix in the sugars. Add melted butter to flax mixture and stir until mixture is smooth.
Stir in maple syrup and vanilla, then stir in flour mixture. Finally, stir in rolled oats and chocolate chips. Dough will be thick.
Scoop up tablespoon-size dollops of cookie dough and place on a nonstick baking sheet, spacing dollops about 2 inches apart. Bake until golden brown, about 10 minutes.
Remove from oven and let sit for a minute or two on baking sheet to firm up. Then, using a spatula, transfer to a wire rack and let cool completely. Repeat with remaining cookie dough.
Store cookies in an airtight container at room temperature up to four days, or freeze in freezer bags or an airtight container for up to two months.
TIP: To prevent the cookies from spreading too much, refrigerate the dough for 10-15 minutes before scooping it onto the baking sheets. Also, while one batch is baking, you can arrange the next on another sheet and refrigerate it till the first batch is done.