Question: What is the centerpiece of a former monastery complex of the Canons Regular of the Lateran, opposite of the chief diplomatic mission of the United Kingdom in Lithuania that represents the British Overseas Territories in Lithuania ?

Context paragraphs:
Embassy of the United Kingdom, Tashkent: The Embassy of the United Kingdom in Tashkent is the chief diplomatic mission of the United Kingdom in Uzbekistan.  The Embassy is located on Gulyamov Street, in the Mirzo Ulugbek district.  The current British Ambassador to Uzbekistan is Christopher Allan.  Diplomatic relations were established on 18 February 1992.  The Embassy also represents the British Overseas Territories in Uzbekistan.

Embassy of the United Kingdom, Stockholm: The Embassy of the United Kingdom in Stockholm is the chief diplomatic mission of the United Kingdom in Sweden.  The Embassy also represents the British Overseas Territories in Sweden.  It is located on Skarpögatan in the Diplomatstaden neighborhood.  The current British Ambassador to Sweden is Paul Johnston.

Embassy of the United Kingdom, Buenos Aires: The Embassy of the United Kingdom in Buenos Aires is the chief diplomatic mission of the United Kingdom in Argentina.  The Embassy also represents the British Overseas Territories in Argentina.

Church of St. Peter and St. Paul, Vilnius: St. Peter and St. Paul's Church (Lithuanian: "Šv.  apaštalų Petro ir Povilo bažnyčia" , Polish: "Kościół św.  Piotra i Pawła na Antokolu" ) is a Roman Catholic church located in the Antakalnis neighbourhood of Vilnius, Lithuania.  It is the centerpiece of a former monastery complex of the Canons Regular of the Lateran.  Its interior has masterful compositions of some 2,000 stucco figures by Giovanni Pietro Perti and ornamentation by Giovanni Maria Galli and is unique in Europe.  The church is considered a masterpiece of the Polish-Lithuanian Commonwealth Baroque.

Overseas military bases of the United Kingdom: This article details the various overseas military bases of the United Kingdom.  The maintenance of overseas military bases enable the United Kingdom to conduct expeditionary warfare, and often tend to be located in areas of strategic or diplomatic importance.  Oftentimes they act as staging areas for the buildup or resupply of military forces, as was seen during the 1982 Falklands War and the use of RAF Ascension Island.  All of Britain's permanent military installations are located on British Overseas Territories (BOTs) or former colonies which retain close diplomatic ties with the United Kingdom.

Embassy of the United Kingdom, Tel Aviv: The Embassy of the United Kingdom in Tel Aviv is the chief diplomatic mission of the United Kingdom in Israel.  The Embassy is located on Hayarkon Street in the Old North area of the city.  The current British Ambassador to Israel is David Quarrey.  The Embassy also represents the British Overseas Territories in Israel.

Embassy of the United Kingdom, Vilnius: The Embassy of the United Kingdom in Vilnius is the chief diplomatic mission of the United Kingdom in Lithuania.  The Embassy is located on Antakalnio Street, opposite the St Peter and St Paul Church.  The current British Ambassador to Lithuania is Claire Lawrence.  The Embassy also represents the British Overseas Territories in Lithuania.

Embassy of the United Kingdom, Beijing: The Embassy of the United Kingdom in Beijing is the chief diplomatic mission of the United Kingdom in the People's Republic of China.  It is one of Britain's largest overseas Embassies.  It is located at "11 Guang Hua Lu", in the Chaoyang District.  The current British Ambassador to China is Barbara Woodward.

Embassy of China, London: The Embassy of China in London is the diplomatic mission of China in the United Kingdom.  The Embassy in London is China's only embassy in the UK, alongside two Consulates-General in Edinburgh and Manchester.  Established in 1877 as the Chinese Legation, the London mission was China's first permanent overseas diplomatic mission.  It has served as the diplomatic mission of the Qing Empire, Republic of China and (since 1950) the People's Republic of China.  It was the location of the Qing Empire's detention of Sun Yat-sen, an important episode in the Chinese revolution of 1911.  It remains today the focal point for events relating to China held in the United Kingdom, including celebrations in 2012 to commemorate 40 years of diplomatic relations between the UK and the People's Republic of China.

St. Vincent Abbey, Senlis: The Royal Abbey of St. Vincent was a former monastery of canons regular in Senlis, Oise, which was destroyed during the French Revolution.  Late in their history, they became part of a new congregation of canons regular with the motherhouse at the Royal Abbey of St Genevieve in Paris, known as the "Genofévains", widely respected for their institutions of learning.

Supporting paragraphs: Embassy of the United Kingdom, Vilnius Church of St. Peter and St. Paul, Vilnius
Answer: St. Peter and St. Paul's Church