Combine 3 oz of the Lindt chocolate with the 2 oz of unsweetened chocolate and place in a microwave-safe bowl. Add the 4 tablespoons of chopped butter. Microwave on high for 30 seconds to soften, then stir to coat the chocolate in butter. Microwave for another 30 seconds and stir until smooth and creamy. If the chocolate doesn’t fully melt, microwave for another 15 seconds.
Allow the chocolate to cool slightly while you stir together the rye flour, baking powder and salt. Set aside.
In the bowl of a stand mixer fitted with a whisk attachment, beat the eggs until foamy. With the mixer going, gradually add the sugar and continue beating for another 5 minutes or until batter is thick and lemon colored. Beat in the vanilla.
Remove mixer from stand and stir in the rye flour mixture. Make sure the batter is no longer warm, then add the reserved chopped chocolate (or bittersweet chips, if you prefer). At this point the batter should be too thin to scoop.
Cover top of bowl and chill until thick enough to scoop (an hour should do the trick).
Preheat oven to 350 degrees F. and line baking sheets with parchment paper.
Using a medium cookie scoop or a rounded tablespoon, scoop cookie dough onto the sheet and bake for 10 minutes or until cookies appear set. Allow the cookies to cool slightly on the baking sheet, then transfer to a wire rack and let cool completely.