trippy_1.rb

# stage 0 build your chef gears
require 'chef'

def run_chef(client, item)
  client.node.run_list.reset!
  client.node.run_list <<  item
  run_context = Chef::RunContext.new(client.node, {}, client.events)
  runner = Chef::Runner.new(run_context)
  runner.converge
end

Chef::Config.from_file '/etc/chef/client.rb'
client = Chef::Client.new
client.run_ohai
client.load_node
client.build_node

# stage 1 do one set of chef run  with recipe foo
run_chef(client, 'recipe[foo]')

# stage 2 do one set of chef run  with recipe bar
run_chef(client, 'recipe[bar]')