1) Preheat the oven to 350°F. Line two baking sheets with parchment paper (for easy cleanup), or leave them unlined; they don't need to be greased.
2) To make the dough: In a medium-sized mixing bowl, beat the butter until light.
3) Add the sugar, vanilla, and salt, and beat until fluffy.
4) Add the flour and stir until a firm dough forms.
5) To make the filling: Crumble the almond paste into a small bowl. Beat in the butter, extract, and sugar.
6) When the mixture is smooth, add the breadcrumbs and mix until blended.
7) To shape the cookies: Roll the filling into 1/4 teaspoon-sized balls.
8) Break off a teaspoon-sized piece of dough, and use your thumb to make an indentation in the center.
9) Place the ball of filling in the indentation, then bring the dough up and over to enclose it, rolling it in your hands to make a smooth ball.
10) Repeat with the remaining filling and dough. Place the bonbons on the prepared baking sheets.
11) Bake the bonbons for 14 minutes. They won't brown; that's OK.
12) Remove the bonbons from the oven, and let them cool on the baking sheet for 10 minutes (they're quite fragile while hot) before transferring to a rack to cool completely.
13) To make the glaze, melt the chocolate in a microwave, double boiler, or saucepan set over low heat.
14) Add the butter and corn syrup, stirring until smooth and glossy.
15) Dip the tops of the cooled bonbons in the glaze. If the glaze thickens, reheat it briefly, then continue dipping. Top each with almond slices or sugar pearls, if desired.
16) Let the bonbons sit for several hours, or until the glaze hardens. Store them in an airtight container at room temperature for several days; freeze for longer storage.
Yield: 60 bonbons.