Heat sugar and water in a small saucepan over medium-low heat until the sugar is dissolved. If needed, use a wet pastry brush to wash down any sugar crystals on the side of the pan.
Increase the heat and bring to a boil without stirring, about 5 to 6 minutes. Until the syrup is a dark amber color.
Remove the sugar from the heat and carefully whisk in the heavy cream. The mixture will bubble. Stir in the unsalted butter and salt. Set the caramel sauce aside, allow it to cool at room temperature.
Preheat oven to 350°F. Line an 8×8-inch pan (or equivalent) with aluminum foil and spray with cooking spray. Lining your pan is highly recommended for ease of cleanup due to the stickiness of the caramel; set pan aside.
In a large microwave-safe mixing bowl, add the butter and heat on high power to melt, about 90 seconds.
Add the brown sugar, vanilla, and whisk until smooth.
Add the flour, oats, baking soda and stir until combined. The mixture will be quite thick.
Add approximately half of the mixture to the prepared pan (you want the mixture to cover the bottom of the pan completely), and smooth it with a spatula or the back of a spoon, to create an even smooth, flat layer; set remainder aside. Bake for 10 minutes.
In a small sauté pan, toast the coconut flakes over medium heat until the flakes are lightly toasted and fragrant, shaking the pan to evenly toast.
After 10 minutes, remove the pan from the oven and evenly sprinkle with the coconut flakes, and then the chocolate chips.
Slowly and evenly pour caramel sauce over the chocolate.
Evenly crumble reserved oatmeal-brown sugar mixture over the top.
Return pan to oven and bake for about 15 to 18 minutes, or until the edges are lightly browned, and the center is bubbling slightly.
Allow bars to cool completely in the pan before slicing and serving, giving the molten caramel time to firm up. This can take up to 4 hours or overnight at room temperature. You can speed it up by placing the pan in the fridge with a sheet of foil over the top.
Bars will keep airtight at room temperature for up to 1 week, or in the freezer for up to 4 months.