In a double boiler or a bowl set over a saucepan of simmering water, add the cacao solids and ½ cup of heavy cream. Stir chocolate until melted and smooth. Set melted chocolate aside.
In a heavy saucepan, combine remaining heavy cream, milk, salt and ½ cup of sugar.
Put the pan over medium heat and let the mixture boil gently to bubbling just around the edges (gentle simmer) and sugar completely dissolved, about 5 minutes. Remove from heat.
Add the Earl Grey tea leaves and let it steep for 7-8 minutes until the cream has taken on the tea flavor, stirring occasionally and tasting to make sure it’s not too bitter.
Whisk in Dutch cocoa until smooth. Add in melted chocolate and whisk until smooth.
In a medium heatproof bowl, whisk the yolks just to break them up and whisk in remaining sugar. Set aside.
Put the saucepan back on the stove over low heat and let it warm up for 2 minutes.
Carefully measure out ½ cup of hot cream mixture.
While whisking the eggs constantly, whisk the hot cream mixture into the eggs until smooth. Continue tempering the eggs by adding another ½ cup of hot cream to the bowl with the yolks.
Pour the cream-egg mixture back to the saucepan and cook over medium-low heat, stirring constantly until it is thickened and coats the back of a spatula, about 5 minutes.
Strain the base through a fine-mesh strainer into a clean container.
Pour the mixture into a 1-gallon Ziplock freezer bag and submerge the sealed bag in an ice bath until cold, about 30 minutes. Refrigerate the ice cream base for at least 4 hours or overnight.
Pour the ice cream base into the frozen canister of your ice cream machine and follow the manufacturer’s instructions.
Spin until thick and creamy about 25-30 minutes.
Pack the ice cream into a storage container, press a sheet of parchment directly against the surface and seal with an airtight lid. Freeze in the coldest part of your freezer until firm, at least 4 hours.
When ready to serve, scoop the ice cream into a serving bowl and top with chopped chocolate.