Place a rack in middle of oven; preheat to 325°. Lightly butter a 9x5" loaf pan; line with parchment paper, leaving a generous overhang on long sides. Butter parchment. Combine chocolate and remaining 7 Tbsp. plus 1½ tsp. unsalted butter in a medium bowl and set over a large saucepan of simmering water (do not let bottom of bowl touch water). Heat chocolate and butter, stirring occasionally, until melted and smooth. Remove bowl from heat and set chocolate mixture aside.
Pulse pecans in a food processor until somewhat finely ground (it’s okay if there are some coarser pieces). Pulse in almond meal and salt; set aside.
Beat eggs in the bowl of a stand mixer fitted with the whisk attachment on medium-high speed until fluffy, about 2 minutes. With the motor running, gradually stream in sugar and beat until mixture is very pale and nearly doubled in volume, about 1 minute. Stream in reserved chocolate mixture and beat until no streaks remain. Remove bowl from mixer and fold in reserved pecan mixture with a rubber spatula, making sure to scrape bottom of bowl, until well incorporated. Pour batter into prepared pan and tap pan on counter to remove any air bubbles.
Bake cake, rotating pan halfway through, until a tester inserted into the center comes out with just a few moist crumbs attached, about 1 hour. Transfer to a wire rack and let cool in pan.
As soon as the cake is almost cool, place chocolate in a medium bowl. Bring cream, corn syrup, coffee, cinnamon, and piloncillo in a small saucepan to a faint simmer over medium heat. Pour over chocolate, whisking constantly until melted and smooth. Add butter and salt and whisk until butter is melted and ganache is shiny and smooth. Let cool until thickened slightly, 15–30 minutes.
Turn cake out onto a large plate or cake stand and turn right side up. Pour ganache over (it should flow over the sides but not quite hit the plate). Scatter chopped pecans over as desired; chill until ganache is set, 10–15 minutes.