平淡 is read as へいたん (heitan) and means simple.
へいたん
heitan
ぴょんやん
Pyongyang (North Korea)
へいおん
tranquil
ひらがな
hiragana
へいぼん
ordinary
へいこう
even scale
ひらまく
rank-and-file wrestlers in the highest division
へいか
normal prices
へいわぶたい
the Peace Corps
へいそ
ひらあやまり
earnest apology
へいし
Heike family
へいこうふせいごう
disconformity