Preheat the oven to 375 degrees Fahrenheit, and line an 8-inch spring form pan with parchment paper.
Melt the chocolate, cocoa powder, and coconut oil in a saucepan over low heat, stirring constantly just until melted.
Remove from heat and add the sea salt, ground cinnamon, vanilla extract, and pure maple syrup. Stir well to combine, transfer chocolate mixture to a mixing bowl, and allow it to cool 8 to 10 minutes.
In a small bowl, whisk together the eggs until well beaten. Pour the eggs into the bowl with the chocolate mixture and stir well until a thick batter forms.
Transfer the cake batter into the prepared spring form pan and place on the center rack of the preheated oven. Bake 30 to 35 minutes, or until cake has set up in the center.
Allow cake to cool for 1 hour before slicing and serving. You can serve the cake with a simple glaze, seasonal fruit, and/or roasted or candied nuts.