The 29-year-old's strike at Villa Park helped the Claret and Blue Army move to fourth on the league table.
His latest effort comes just three days after hitting a double to lead Villa to a 2-1 triumph over Queens Park Rangers on Saturday.
Against Sunderland, Adomah opened the scoring in the 10th minute, tapping in at the far post after Robert Snodgrass delivered a fine cross.
Four minutes after recess, Joshua Onomah sent Villa 2-0 up with a strike from 20 yards.
Lewis Grabban, however, ensured that Sunderland did not leave Villa Park without a consolation as he netted in the 72nd minute to reduce the deficit.
Villa have now fetched consecutive wins in their last two games since their shocking 2-1 home defeat to Sheffield Wednesday in the first week of November.
On a personal level, Adomah has now registered eight goals in 11 championship starts this season, and nine goals in all competitions, having netted once in two League Cup outings.
His first three appearances for Steve Bruce's outfit this season were from the bench.