I think one of the most important things about making chicken adobo is reducing the boiling liquid after the chicken has been cooked. My method for doing this is pouring all the liquid into another pot then heating it boil out the water. Once the water has been reduced the next thing I do is add a thickener. I like using a French cooking technique called Beurre Manie which is flour mixed with cold butter. The beurre manie looks like play dough. I add some beurre manie into the cooking liquid and it thickens the liquid into a nice gravy consistency.