PREHEAT THE OVEN TO 350 DEGREES.
ADD THE GROUND BEEF TO A LARGE SKILLET AND BROWN OVER MEDIUM HEAT.
SPOON THE BEEF OUT OF THE SKILLET INTO A GLASS BOWL AND ADD THE BUTTER, ONIONS AND PEPPERS.
COOK FOR 4 MINUTES STIRRING HALFWAY THROUGH.
ADD THE BEEF BACK INTO THE PAN.
ADD THE KETCHUP, WORCESTERSHIRE SAUCE, SALT AND BLACK PEPPER TO THE MIXTURE AND STIR.
STIR IN HALF OF THE SHREDDED CHEDDAR TAKE IT OFF THE HEAT AND SCOOP IT INTO THE PASTA SHELLS.
USING THE SAME PAN ADD THE BEEF BROTH, MILK AND CORNSTARCH AND WHISK BEFORE TURNING THE HEAT BACK ON.
ADD IN THE REST OF THE CHEDDAR CHEESE A LITTLE AT A TIME WHILE WHISKING FOR 3-5 MINUTES OR UNTIL THICKENED.
POUR ABOUT HALF THE SAUCE AROUND THE SHELLS.
BAKE IN THE OVEN FOR 10 MINUTES TO MELT THE CHEESE.
SERVE WITH REMAINING SAUCE.
ENJOY!!