Make the dough by adding flour, oil, and two eggs in a stand mixer, and start mixing the dough on low speed.
Gradually add water if needed until the ingredients are well combined.
Attach the dough hook to the stand mixer and knead it until the dough is no longer sticky.
Wrap the dough in plastic wrap and let it rest in the refrigerator for an hour.
Meanwhile, take a medium mixing bowl and add ricotta cheese, mascarpone cheese, two tbsp of sugar, chopped chocolate, the remaining egg, vanilla, and cocoa powder.
Use a whisk to thoroughly combine everything.
Cover the prepared filling with plastic wrap and refrigerate it until firm (about an hour or two).
Divide the dough into four equal pieces. Using a pasta machine or rolling pin, roll the dough pieces into long, thin sheets.
Lay down each pasta sheet on a lightly floured surface.
Place one teaspoon of the filling across the sheet, leaving about three inches of space between each of them.
Fold the dough over the filling and seal them by pressing your thumb around the outside.
Cut each of your agnolotti and set them on parchment paper.
Cover them with plastic wrap and freeze the chocolate-filled agnolotti for 15 minutes.
Meanwhile, simmer water in a deep pot with the remaining sugar.
Add the agnolotti and let them cook until they float.
Use a slotted spoon to remove the cooked agnolotti.
Serve them with a dusting of cinnamon sugar and enjoy.