Mexican Turtle Chocolate Mink

Put oven rack in middle position and preheat oven to 350°F. Butter 2 oven-safe bowls or ramekins.
Melt chocolate and butter in heavy saucepan over very low heat, stirring until smooth. Remove bowl from heat and cool, stirring occasionally, 5 minutes. Whisk in egg yolk, salt, and ground cinnamon until combined. Beat egg white in a bowl with an electric mixer at medium-high speed until it holds soft peaks. Gradually add sugar, beating, and continue to beat until white just holds stiff, glossy peaks. Whisk about one fourth of white into chocolate mixture to lighten, then fold remaining white gently but thoroughly.
Divide batter between bowls or ramekins. Cover each bowl with small squares of foil and crimp foil tightly around rim. Place a baking dish in oven and pour hot water (easiest with a teakettle) into dish. Carefully place ramekins into baking dish. Make sure foil is above water. Bake until puddings are set, about 30 minutes. The desserts will be slightly gooey to the touch.
Transfer bowls to a rack and cool puddings, uncovered, about 1 hour. Just before serving, unmold puddings into serving bowls or onto a plate. First, unmold desserts by taking a knife and running it along the edge of the ramekin. Second, place ramekins into a bowl with hot water for about 15 seconds. Turn ramekin upside down and tap bottom. Top each pudding serving with 2 tablespoons of cajeta and 2 tablespoons of chopped pecans that have been toasted.