Step 1

Take lamb out of fridge at least 1 hour before roasting. (Note 2)

Step 2

Rub: Combine rosemary, garlic and olive oil. Mix and set aside for 20 minutes+.

Step 3

Preheat oven to 220C/430F (fan forced / convection) (Note with oven shelf in the middle.

Step 4

Place garlic cut side up in a roasting pan. Toss in rosemary sprigs.

Step 5

Turn the lamb over so the underside is facing up. Pour half the Rub on, add a good sprinkle of salt and pepper. Rub all over.

Step 6

Transfer into roasting pan, placing it on the garlic to elevate the lamb. Rub remaining rub + salt and pepper over lamb.

Step 7

Roast lamb for 20 minutes then turn down to 180C/350F (fan forced/convection) (Note 4). Roast for 1 hour - total of 1 hr 20 minutes.

Step 8

Remove lamb from oven. The internal temperature should be 55 - 60C/131 - 140F for medium rare (pictured). This will rise to 61 - 65C / 142 - 151F after resting. See notes for cook times - Note 5.

Step 9

Transfer lamb to plate, cover with foil and rest for 20 - 30 minutes.

Step 10

Make gravy straight away while roasting pan is hot.

Step 11

Remove rosemary sprigs. You should have around 4 - 5 tbsp of fat. If less, add butter. If much more, discard a bit.

Step 12

Place roasting pan on stove over medium heat. When the fat starts to bubble, then add flour. Mix flour in and cook for 1 minute.

Step 13

Pour in half the beef stock and mix to dissolve sludge in, then add remaining beef stock and mix.

Step 14

Use a potato masher (if you're really keen like me) to mush the garlic to squeeze out the flavour.

Step 15

Add salt and pepper to taste.

Step 16

Simmer for a couple of minutes, stirring, until it starts to thicken. Take it off the stove BEFORE the gravy is the thickness you want because it will keep thickening.

Step 17

Strain into a bowl, mushing garlic to squeeze all the liquid out. Then pour into gravy boat.

Step 18

Serve lamb with gravy on the side, peas and Truly Crunchy Roast Potatoes. (Note 6)