Mushroom ketchup works to a large extent by adding umami - the fifth taste according to some, or naturally occuring MSG to others.
Godo stuff, although I don't rate it as a cure-all to solving all your flavour woes. Missfran's right to a large degree - you'll never make a pasta sauce that tastes quite like salt and sugar filled Dolmio, just as you'll never be able to replicate a BigMac at home - but it's also worth checking you're cooking everything to the best of your ability as well. With the beef burbouignon (Sp) make sure you brown the meat well at the first stage for example, scraping and 'deglazing' the pan as you add the alcohol/stocks/liquids to get a full flavour.