In large pot-Place roast add all seasonings, peal and chop onion, place in pot...completely cover with water...cook on medium high to high for about 3 hours...
Once roast is done, falling apart, remove from pot and set aside to be shedded later, drain about half the broth, place remaining broth back on heat and bring to boil...mix 2-4 tsp. flour with 1/2-1 cup warm water(to make a thickner for the broth)..add to boiling broth stirring consintly until pretty thick gravy...turn heat to very low and simmer
while gravy is simmering, shredd roast...add shredded roast, 2 cans drained sliced carraots...let simmer
mix 2 boxes potatoes as directed...let cool.
in large/deep roasting pan or bowl add meat/gravy mixture (should be pretty thick)< using large freezer bag, fill with cooled mashed potatoes..snip a corner of bag with knife or scissers and pipe mashed a top meat/gravy mixture
bake in pre-heated 375 degree oven for about 20 to 30 minutes or until lightly brown and bubbling around the edges!
let cool slightly and serve with can of flakky butter cresent rolls!