A framework that boosts the imputation of 'missForest' by Stekhoven, D.J. and Bühlmann, P. (2012)

Missing Value Imputation in Parallel
install.packages("misspi")
Please find a more detailed tutorial here
data(toxicity, package = "misspi")
set.seed(0)
toxicity.miss <- missar(toxicity, 0.4, 0.2)
toxicity.impute <- misspi(toxicity.miss)
toxicity.impute